Sandru, New Vegas is definitely worth a play-through, just think of it as a large expansion pack rather than a true sequel. The gameplay quality is at least as good as FO3, and the writing and quests are much better. I think there are something like 2-3x the number of quests as FO3 and most of them are quite interesting. One other thing the game did really well was give you several large scale moral choices that directly affected the outcome of the game, and the society. NV is one of the few games that has done this right.
I don't remember the game being terribly buggy but I do remember tons of invisible walls; Nothing was more infuriating than climbing a mountain only to not be able to reach the summit because it was surrounded by invisible walls, and the devs didn't want you to get there before the related quest. Also, lots of high-powered enemies that prevent you getting to certain areas too early. Fucking cazadores.