Beautiful watch. Definitely smaller than F3. Not crazy about 22mm band. Wish it was 24mm. Rainy run with lots of clouds. Recorded distance spot on, but track isn't the best ive seen for sure. HR worked well but started getting too high near the end. I believe water on sensor threw it off. F5 throws out some neat stats at end of run too, like Aerobic vs Anaerobic training, Vo2 Max, and recommended rest. All in all, I think this is a solid improvement over the F3 but I wish the strap was wider! Also it has disconnected a few times at random with my iphone and yes, after Sync it turns off the vibration alerts for some reason....
Oh, I also uploaded a route via Garmin Connect and it followed it like it should, along with Turn-by-Turn directions which was pretty nifty!
https://connect.garmin.com/modern/activity/1633073575