I think that it is adequate for regular runners who want to improve their training or riders who need a boost of motivation. For true athletes and performers, the model of the type 310 (or other 600 -> 900) will be more complete.
Bezel (sensitive dial): I had a fear due to various negative opinion on the web overlooked the dial, but personally I do not find it annoying that I prefer buttons. I think it should not be a reason for exclusion; Get used to use it and it's going fast enough. By cons actually I doubt that it works with gloves.
Portability: It's still much bigger than a standard watch (although it is fashionable clocks on wrist currently), however the watch remains in cell day (for men anyway). But if you want a discreet watch is missed.
Information by race: it is possible to configure 3 info fields simultaneously on one screen (but you can also travel on multiple screens in the race course). 4 fields would be more convenient, but one could read anything; why you need a giant dial as the 310 is no longer truly portable disqualified.
Advantage compared to the 110/210: clearly is the possibility to import routes (eg split) of the PC to the watch. It's very simple to do using "training center" on PC. Personally I think it misses the 110/210, but there is nothing for nothing.
Other: reminder, it can not be used in swimming A site (in English) for a tour of the question!:
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AN complete presentation; The author is not positive with respect to the watch, but it was much more expensive at the time of review, and it does not support dial :-) sensitive (and it makes triathlon).