Over the past few weeks, I’ve had a chance to try a few more outdoor GPS running watches, including the Garmin Fenix 7, Coros Apex 2 Pro and Suunto 9 Peak Pro. After using Coros Pace 2 watches as outdoor GPS references almost exclusively for many months, I have quite a few thoughts to share. While I have full reviews upcoming, I want to discuss the Garmin Fenix 7 in particular, as it’s impressed me so far.
This $699 watch comes in at roughly double the price of the Coros watches, and it’s even more expensive than the Suunto and Polar watches (unless you get the refurbished version, which is slightly cheaper). While it only has a single GPS chipset, it is a more advanced Airoha AG3335M (as opposed to the standard AG3335 used in all other watches mentioned here). I’ll discuss the GPS accuracy in more detail soon, though, as that has left me the most impressed about this device.
You are trading some other features, such as lightweight design (on the Coros watches), extended battery life (Suunto 9 Peak Pro), and the ability to track multisport triathlon activities (Garmin Forerunner 955), but there are also a few key benefits to the Fenix 7 — in particular, the mapping capability and the completely integrated Garmin Connect platform with years of training data history.
While each watch certainly has advantages, and I would argue that the Fenix 7 has the most developed platform (due to it being from a larger and more established company), I have been very impressed with the device’s GPS performance, so let’s discuss that!
All the other watches I listed use Airoha GPS chipsets, but they use different models. Coros uses the AG3335, Suunto uses a similar dual-frequency chip, and Polar uses the AG3335. However, despite the naming scheme, each of these chipsets has very similar performance, with the key differences being in software processing and multi-band support. On the other hand, the Fenix 7 uses the Airoha AG3335M with multi-band support.
Which of these chipsets is more accurate is still up in the air, as some studies point to the multi-band GPS performing better while others have found better performance with single-frequency chips in open conditions. Either way, I tend to look at the chipsets as roughly comparable — at least for open road running.
Laboratory Performance Evaluation of a Low-Cost Electrochemical Formaldehyde Sensor - PMC
I wanted to make some comparisons, so I decided to graph the GPS distance recorded by the Fenix 7 and a couple of Coros watches over the same routes. At first, I found that the sensors recorded slightly different distances, but after doing some research, I found it’s common knowledge that the Coros watches (and likely most single-frequency devices) can underreport GPS distance in heavy tree cover. For this reason, Garmin developed a multi-band mode to bring their readings more in line with professional survey equipment (at least for trail and urban running).
Before the multi-band correction. Please note that Coros Apex is mislabeled (it should be Coros Pace 2).
After multi-band correction. Also, sorry for the imperfect comparison graphs…
After exporting data that had been corrected for tree cover, I was surprised to find that the Fenix 7 with multi-band GPS and the Coros watches showed very similar readings in open conditions. While I’m unsure what corrections Garmin applies, I was impressed at these results and, while I lack access to professional survey equipment, I would take this to mean the Fenix 7 GPS accuracy is excellent.
A full review is coming up soon, but I was impressed to see the similarities in readings in open conditions, and I think the Fenix 7 might be another great (albeit higher cost) outdoor GPS running watch option!
