Although I now always use my Forerunner 920XT instead of the Suunto Ambit 2S I still like movescount.com better (I made a small tool that uploads Garmin .FIT files to my movescount.com account in the name of my old Ambit 2S). I use those watches for windsurfing and the 3 reasons are:
1) when selecting a part/section of the track, then the min/max/avg values get updated to the made selection. This is handy when looking at a jibe or turn to see what the minimum speed was for example.
2) although the fr920xt .fit files contain 1-sec records the track on garmin connect visualizes points just every 4 seconds or so. At turns a lot of info gets lost when looking at the track. At least when the sport is set to Wind/Kite Surfing, then it should visualize records every second (as in the original track).
3) movescount.com allows to upload images and attach them to tracks. It's nice to look at them later and to remember a nice session.
Here is my movescount.com account:
http://movescount.com/members/mete
and Garmin connect account:
https://connect.garmin.com/modern/profile/FIN151
With the same tracks in case someone wants to compare.
Thanks and greetings,
Mete
PS: I got a huge fan of the fr920xt, imho it is better than the Ambits.