Re: factions: 1997's Hart Foundation takes the cake for me as the best of these and the high point of Bret Hart's career. The thing with the Horsemen is that they went through so many iterations that it's hard to have a completely sunny view of them. Some of those iterations are probably better than the Hart Foundation, and some had Paul Roma involved. There's only one iteration of the Hart Foundation as a stable, and it had Bret Hart on top of his game and Owen Hart as a strong #2. At this point in their careers, it's hard for me to say that they weren't better than Flair and Arn- maybe it wasn't Owen's peak as a performer, but it wasn't like Owen Hart had too many bad matches ever. Pillman was past his peak (actually, he was nearer his peak when he was a Horseman!) but Bulldog was a solid #3 or #4 - depends on where you rank him with Pillman at that time in his career- than, say, the Nation of Domination ever had. Neidhart as your fifth guy is not a bad fifth guy at all, but you obviously don't want him higher. #3 and #4 of the Horsemen were certainly better than this in their best iterations, but this may be a diminishing returns sort of thing after the first two- it really depends on your point of view and I'd accept either stance.
They even had a few defining matches, most notably the Calgary Stampede 10 man tag match, but Bret vs. Undertaker at Summerslam 97 is what made me a fan of that era of wrestling for life- gotta confess I haven't watched in almost 10 years now.
The best iterations of the Four Horsemen had to be better at the time, but they sort of dragged their legacy through the mud to the point that they're "just" number 2 for me. Flair had plenty of classic matches, so did the Minnesota Wrecking Crew, but don't bring up their alliance match with the Dungeon of Doom, please.
I didn't watch much WCW at that time (again, was a Bret Hart fan) but the NWO always seemed overly bloated after you got past the initial 3 or 4 guys. Definitely influential and something everyone remembers, though. But what's the best NWO match? Isn't it Bash at the Beach 96, which is, you know, a tag match?