I tried the updated Garmin Express today. The Garmin swim watch transferred the data, displaying "data transfer" on the watch, then it displayed the time, Garmin Express on the computer said "sync complete". Then the whole "data transfer" started again with the "sync complete" message on the computer as well. It did this about 10 times before I removed the watch from Garmin Express. It appeared to be stuck in a loop, and I was afraid this loop would kill the battery. Garmin Connect showed the data after the first transfer, so I don't know what it was trying to send.
UPDATE!
I was checking the Garmin Express version, it was 3.0.6.0, and a message said there was a new version. I am installing 3.0.7.0 right now and will report back if the same thing happens after my next data transfer.