I will share here only my experience, it may be subjective, I am not urging you to buy Trex or other watches, just my user experience.
I use an instinct 2 solar, from the beginning I want to tell you not to buy "solar" products from garmin, it's just a sales trap, it doesn't work, example:
the watch normally loses 3-4% battery per day, I charged it for a day only in the sun, I collected +30% battery from the sun, it sounds good.
then the curtain 5-7% per day, I think you get the idea :)
ok, I did direct tests with both watches, one on one hand and one on the other hand (instinct 2 solar / Trex2).
for gym training without putting the exercises only on automatic detections, both instinct and trex are not accurate, both are wrong when counting the exercises, for gym exercises they are equal, I didn't see the difference.
the biggest problem with instinct is pulse detection, during training after finishing an exercise it shows my pulse much lower than trex, example: after finishing the exercise I feel that I am very agitated, instinct shows me 100 beats and trex shows me 150, then I rest and the trex goes down and the instinct goes up, and at 139 beats both meet, that means garmin has a big delay and doesn't look right, those who have heart problems can be a fatal factor.
I also tested GPS, I did a race with both watches, both have small deviations from the race, it's something normal, I classify them as equal in this sense.
I haven't checked the compass because I don't use it, I tested the storm alert, with Trex you can change the sensitivity of the barometer and it will warn you even when a little rain comes, with Garmin there is a storm alert, which is often not the case, you have the alert but it doesn't it's raining, here I give priority to TREX2, I can change the sensitivity to see a little rain or change the sensitivity and show a puerile storm.
I know that Garmin pays a lot for all the licenses of the watch, I don't know about Trex, it's from xiaomi after all and it's possible that all the Chinese just steal without paying, only that it works no worse than garmin.
I can compare trex2 with EPIX pro 51mm from garmin, only there is a problem, you can buy trex 2 on ebay for 80 lire used or 150 new, or on the official site for 220 lire, but an epic pro 51mm costs 900 lire at a discount.
try, test, the Chinese are coming hard with their products now, and with very funny prices compared to garmin.
I'll tell you from the start that I only tested the trex2, it's the same size as the epix/fenix 51mm, it's not a small watch.
all the best !
