I have the 910 and generally like it. I too have noticed that the pace jumps around wildly. But the average pace data at the end seems accurate. Right now, I'm doing my training by heartrate and not pace, so it's not as critical for me that the instantaneous read of pace be accurate. I'll care more about that later when race season starts, so I hope there's a firmware update soon.

Otherwise, I love the 910. The swim data is unfrickin' believable. The only thing it *doesn't* know is your pace/distance on kick sets indoors, since you aren't moving your arms. Other than that, I've only had it lose 25 yards once or twice on an interval. I think it uses an accelerometer of some sort to figure out when you've turned, and since my turns totally suck, it probably didn't sense it.

Unfortunately, the Garmin Connect website does not allow you to edit the workout info, so the history on the website is wrong. I suppose one could download the file to .csv, edit and then re-upload, but that would be a PITA. I download the file as a .tcx and upload it into the coaching software my coach uses. That software lets me edit the file for distance, etc, though it doesn't use all the cool data like the swolf scores, etc.

I'm really looking forward to using the unit for open water swim training. I probably don't go nearly as far as I think I do when I'm out at the lake... It will also be interesting to see how crookedly I swim in open water!