I used the quick release mount for about 2 years, until it started releasing when I went over big bumps; I launched that Garmin more often than I care to remember and it's no fun searching the side of the road hoping that the thing can be found and is still working. Now I use the rubber mount. For my triathlons this means leaving my older 305 on the bike and using my 310 on my wrist for everything else.