Sigma ROX 12.1 EVO Review: New But Already Outdated?

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Sigma introduced ROX 12.1 EVO a few months ago. A new flagship computer that should provide a top-notch navigation experience. Is that really so? In this review, you’ll find out!

I’ve been using it for the last few weeks to find out how easy to use it is, what features it offers, and most importantly, how it compares to Garmin, Wahoo, and other best bike computers.

My ROX 12.1 EVO rating at a glance:
Battery Life 2/5 | Ease of Setup 5/5 | Display 4/5 | Ease of Use 4/5 | GPS Accuracy 3/5 | Maps & Navigation 5/5 | Price 3/5 | OVERALL 3.7/5
More about this bike computer scoring.

Sigma ROX 12.1 EVO Pros & Cons

These are the main pros & cons of ROX 12.1 EVO I found during its use.

What’s New Compared to the ROX 12.0 EVO?

Unboxing & Setup

To set 12.1 EVO up, you must download a smartphone app and scan the QR like on Wahoo ELEMNT bike computers.

Then, you pair the sensors, and you are good to go. However, I always go through settings to learn more about the possibilities and adjust data fields.

I like the possibility of changing the number of data fields displayed and their layout. Everything can be done directly on the device or in the Sigma Ride app.

My Experience

Let’s now talk about individual features in more detail.

Display

The Sigma ROX 12.1 EVO’s display is 3 inches, with a resolution of 240×400px. This means the resolution is slightly better than that of Garmin Edge 540 or 840 bike computers.

It’s still a touchscreen, but despite its size, it feels compact. However, even after a significant redesign from the previous generation (ROX 12.0 EVO), I still find the bezels too wide.

The weight of 110g is surprisingly high. For comparison, BOLT v2 weighs 68g, Edge 840 85g, Karoo 2 131g, and Edge 1040 126g.

The ROX 12.1 EVO has decent readability but relatively low brightness and not-so-contrasty colors. I can still read everything in direct sunlight, but I can imagine that people with poor eyesight may have issues. Its finish is also glossier than Wahoo computers, reflecting more glares.

It has an ambient sensor, so it can adjust the brightness based on the outside light conditions to save battery life.

The ROX 12.1 EVO can fit up to 10 data fields on one data page, and you can also choose from multiple layouts available for each data page.

It’s a shame that it can’t zoom in and out through data fields like ELEMNT computers to make the data fields larger or smaller.

On the other hand, you can customize the background color of each data page to color code the same types of data (watts, HR, speed) or match it with your bike’s color. This is honestly a cool feature. Furthermore, this setting is more flexible than on most bike computers. It’s one of the highlights of 12.1 EVO.

Battery Life

The claimed battery life of ROX 12.1 EVO is up to 14 hours, which is low in 2023. I would expect at least 20 hours. I hate recharging a bike computer every week or two.

The question was: How long will it last in standard use (with HR monitor, power meter, cycling radar, and phone connected)?

I was able to squeeze about 13 hours and 24 minutes from it. For comparison, Edge 840 lasted about 24.25 hours during my testing.

This bike computer has a battery saver mode but is only available when an activity is in progress. You can access it by pressing the power button.

It would also be great if Sigma could display the remaining battery life when the device is turned off. The small icon at the top of the screen can be easily missed.

Lastly, it’s important to mention that 12.1 EVO has a USB-C charging port.

Control & User Friendliness

The ROX 12.1 EVO offers several significant benefits, including ease of use. Although it may not match the Wahoo ELEMNT’s level of simplicity, it provides more extensive functionality.

The Sigma head unit is user-friendly and boasts a touchscreen and button-based controls. You can choose the one that suits your preference or combine them.

What’s impressive is the responsive display and powerful internal components, ensuring a smooth experience throughout the system without any lags. For comparison, I noticed that Edge bike computers become sluggish when using long courses.

During testing, I also checked the touchscreen’s reliability in wet conditions and while wearing full-finger gloves. While the display handled my full-finger gloves well, it struggled with water. Watch the video below.

However, I noticed that the smartphone app lacks some settings, such as WiFi connections and map downloads. It would be great if Sigma unified this experience.

Maps & Navigation

The ROX 12.1 EVO’s main focus is on cyclists who value excellent navigation, so I was naturally curious about it.

The good news is that you can conveniently download and update maps wirelessly, unlike on Garmin Edges.

Moreover, you can prioritize road types for navigation, like favoring tarmac over gravel or dirt roads.

With 8 GB of internal storage, you can download numerous maps. For instance, the UK map takes up 480 MB, while US states range from a few MBs to a few hundred MBs, and Germany occupies about 1 GB.

While using the Sigma ROX 12.1 EVO, I encountered confusion when setting a home address. The available countries for selection were limited to downloaded maps, so I had to download the map of the Czech Republic first to set my home address.

On the positive side, loading and calculating routes takes only a few seconds, and the turn-by-turn instructions appear at the right time.

However, the biggest drawback is that this head unit lacks a ClimbPro-like feature. But Sigma is working on introducing it soon.

Notably, the ROX 12.1 EVO offers multiple navigation options. It can guide you to Points of Interest (POIs), a selected point on the map, back home, a preloaded route, and more.

I like the “Draw my route” feature. You can draw a route on the map, and the navigation will do the rest.

Accuracy

The 12.1 EVO doesn’t support multi-band GNSS satellite systems as the higher-end bike computers. So, how does this translate into GPS accuracy?

I went to my favorite segment in the forest, where I test all the bike computers. The accuracy was pretty bad. The ride recorded was completely off-road in a few places.

I honestly don’t understand why a navigation-focused, flagship bike computer doesn’t have multi-band GNSS.

Connectivity

Sigma ROX 12.1 EVO has ANT+, Bluetooth, and WiFi connectivity. It can download and update maps wirelessly.

You can pair it with additional sensors, such as HR monitors, power meters, cadence and speed sensors, bike radars, or electronic groupsets.

Of course, ROX 12.1 EVO can automatically upload your activities to 3rd party apps like Strava or TrainingPeaks or control your smart trainer.

Sigma ROX 12.1 EVO Alternatives

Sigma ROX 12.1 EVO Technical Specifications

Here is the summary of the main features and the technical specification of the Sigma ROX 12.1 EVO.

My Verdict

The Sigma ROX 12.1 EVO is a bike computer that appeals to a very specific group of people. Despite being a new flagship model, it lacks some features commonly found in cheaper bike computers, like the ClimbPro-like feature* and multi-band GNSS.

*Sigma is working on adding such a feature, but they haven’t confirmed when they will release it.

I like the flexibility the interface offers when adjusting data pages and fields. It’s on par with, maybe even better than, the Hammerhead Karoo 2 interface.

ROX 12.1 EVO is cheaper than Garmin Edges (840 and 1040) but more expensive than the compact yet similarly capable Wahoo ELEMNT BOLT v2 or less-known Chinese alternatives.

Personally, I don’t belong to the group of people considering buying the EVO 12.1. This bike computer is more suitable for those who appreciate sophisticated navigation features, e-bike riders, and those who don’t mind short battery life focused on performance.

Maybe I will change my mind once they introduce the ClimbPro-like alternative. But I started to hate bike computers that need to be recharged weekly.

After considering all the pros and cons, I believe this head unit’s price-to-performance ratio is not favorable. This is true even though there is a significant difference between the Sigma 12.0 EVO and 12.1 EVO.

However, it’s worth noting that these two versions are five years apart. I think Sigma missed a chance to make a bigger impact and introduced a head unit that is already outdated in some areas.

Sigma ROX 12.1 EVO FAQ