I haven't had any problems with PUGs either, could it just be a US server problem? (not likely, I must just be lucky) Most of the time we've completed the mission/quest we've started, with only 1-2 droppers now and then, and we have completed the missions even after some dropouts most of the time. Sure, the action isn't as smooth as with a well balanced guild team etc. (one might even say a cookie-cutter team) but that's just what keeps my interest in the game, each person has their own style of finishing some missions and it's always refreshing to do missions in other ways than how one has grown accustomed to.
It's all about observing the team chat before entering a mission/explorable area, discussing how people are used to do play the mission/quest at hand and of course kicking those who join groups just to open a trade during a mission to sell you something
Sometimes PUGs do lose missions, but it's not something to be afraid of. It's one of the ways to spot the ragequitters and those without any kind of patience whatsoever, you can always try again without those rotten apples spoiling the fun
Oh yeah, I'm on European servers too...

By good, what I really mean is a group of team players. I often tell people that the difficulty of a mission or quest depends, more than anything, on your party.

