So far most of the groups I've been in have been fine, and I don't mind a handful of wipes because I know that people are still coming in/learning the fights.

That being said, we had an entire alliance (minus one poor NIN) drop after the 1st boss and before the 2nd last night. Not after a wipe, but after a successful clear. Pretty sure they were all trolls, as most of them were in 'base' classes (CNJ, WAR, etc) and glamoured naked... kind of annoying for trying to get the first boss down, tbh.