Ok, so I looked at the Garmin 910. Here are the differences I see:
For anyone using the Garmin...can you answer this? Is the bulk still make this viable to use when racing? Also, does the bulk in the watch mean no external GPS sensor like the Polar has?
No need for an extra GPS gadget with Garmin - it's already included in the watch. Furthermore, it tracks all your indoor AND outdoor swimming, with distance, stroke count, swim style, etc. And with the GPS included you really don't need any of the other pads or pods. The only advantage of Polar is that it measure heart rate during the swim - which I don't think is so important.
But the Garmin appears to be very large. Does the size cause any inconvenience for races or training? Also, how is the software for the Garmin in regards to tracking all of your statistics? I am really looking for my own "personal trainer" or "training buddy" with whatever option I go with.