ok, found another buggy quest (maybe it;'s not the quest itself so much as the game's engine reacting to certain things or occurrences). the one with sgt. Contreras, the infamous NCR quartermaster. his string of quests is supposed to give you access to his "secret stash", well the game lets you finish it, yeah. but at some point it stopped feeding me updates, whenever I'd close a part of the quest, it would play me the soundeffect but wouldn't show any text or give any xp. so, when it was all over, I came back to Contreras for my reward and he acted like we first met, only there was still an option "So, where do I find Price, again?". no access to his special list, however... well, that was a complete waste of time.
also, I'm really disappointed by the Van Graffs' quest. I let them kill Cass hoping the game would give me a chance to avenge her. it's a real bummer there's no option to side with the Legion at the warehouse. what's more, you can't just come and kill them all, you'll lose Freeside fame if you do. and to top it off, everywhere I go I end up helping NCR, which is exactly opposite of my intentions.
now I'm trying to figure out if anyone else needs the Gun Runners' manufacturing plans.