We really enjoyed the tour. However, it was a good day. Not too cold, no rain, and a little cloudy so we saw the "blue" Glacier with a only a handful of visitors. I was told the group that came last week wasn't so lucky. So, your mileage may vary.
The tour guide (bus driver) was very knowledgeable and gave us very good tips on what to expect, what to do, where to eat etc. Very helpful.