1) better battery life - teh previous FR450 was marginal on battery for soem of my longer distance bike rides
2) the multi sport stuff - I was planning a duathlon this year and it looked so much better for that. Haven't done one yet as the tri clubs round here are a real rip off compared with the running clubs
3) It looked cool
What I've found since I bought it is
1) it still looks cool
2) great on battery life, I can charge it before I go away for a week adn not worry about it.
3) much better data available just on the machine itself before I download when I get home from a trip
4) great GPS sensitivity, and speed of pick up
5) much easier to swap onto the bike with the quick release kit and swaps between bike sensors easily
6) better display
But the really cool feature I've found recently is the interface with other gym kit. At home I have, in addition to three bikes, turbo trainer and weights bench, a concept two indoor rower.
I bought it second hand and it's a very old model C (if you are familiar), originally fitted with the first generation PM1. I replaced that one with a PM2, still older tech, but worked very well until it died this winter. Replacement choice was the better, but still limited PM3, or the latest tech PM4, with ANT+ technology, same as the Garmins.
Seeing someone else manage to link the two sealed it for me, PM4 it was, now to make the case to the centra accounts department (aka the wife). Basically these thinsg hold their value extremely well, they're bulletproof and change hands within the rowing community pretty easily, in fact I could probably sell mine now for much more than the very good deal I got originally.
So PM4 it was, sourced one locally, and at lower price than concept 2 were selling it. Now to try and synch them. To do so, I ended up having to go right back to C2, with instruction from those who had gone before me, and get the as yet unreleased beta firmware downloaded.
Whoa, this looks really cool, not only can I now synch the HR belt but the entire 310XT, which slaves itself to the PM4, so set up the workout on teh PM4, pull the handle to start rowing and the 310XT automatically start it's timer. Finish and the 310XT stops. The best thing however is that it also records the splits for you.
Yesterday that was a superb feature as the planned workout was 20 x 45" hard/ 15" active rest, which would previously have had me flapping around at the lap button each time whilst trying to suck in air between intervals in only 15 secs.
The 310XT however behaved impeccably and not only started and stopped itself, but recorded every split as well including
1) HR max and average
2) Power - max and averge
3) Stroke rate - max and average.
The only thing that let it down (and I can't fault it for this) is the resolution on the Garmin, which is designed for running/biking, only gave 1 dp i.e. 0.2km, or 0.21km, whereas I was looking for 195-213m on each interval, so I still had to get that data from the PM4 by hand, but overall a great experience.
The workout still hurt though, it hasn't done anything about that.
Screen shots and links
The warm up http://connect.garmin.com/activity/97687429
I foresee more fun with this