I didn't have any trouble with the first 3 dungeons with the exception of my very first run through Sastasha and that was the fault of a lone LNC that refused to take any advice. We got all the way to the end with little fuss (stupid LNC pulls didn't help but we managed) but the last boss ROFLstomped us a few times because the LNC refused to do anything but attack the boss. He wouldn't kill adds, or click bubbles (as we later learned) and he didn't know how to use his LB so we had a double LB just going to waste. Eventually I popped my defensive LB and we rode the storm out, but we only won via luck. I was 1 hit from death for the last 10% of the boss, and a good grouping of parries and dodges saw us through.
That is as close to a bad experience as I have had yet... now I run with a fairly standard crew and we wreak house, so no worries there. When I do PUG, it isn't terrible... the only thing I can't get passed is the impatience of people. I mean FFS, let me catch a breath and mark a target already!
"On a mountain of skulls in a castle of pain, I sat on a throne of blood. What was will be, what is will be no more. Now is the season of evil!"
~Vigo the Carpathian