What do you guys think is a more entertaining fighting game. MUGEN or Project M?
For those who are unaware MUGEN is a 2D-fighting game where anyone can create and upload custom content like fighters/stages/etc. so one can have fights like Ronald McDonald vs. Godzilla.
Project M is a mod of Super Smash Bros. Brawl (I don't know how they did it) that allows anyone to create custom characters.
They are two very different games. As mentioned, Project M doesn't really have custom characters created by "anyone" – there's a very tiny number of extra characters, and the whole thing has been very meticulously balanced and tweaked for the hardcore Smash Bros community (or at least that's what I understand they're aiming for). That said, in the end it's still Smash Bros and if you've already played it to death I can't really see the appeal.
MUGEN is just a whacking huge hot mess. You can probably get just as much enjoyment out of watching the Youtube vids. (There's a pretty popular thing on Twitch these days called SaltyBet that lets people bet on random MUGEN matches.) Yes, there are a lot of characters, but there's definitely a huge variation in quality and pretty much nothing has ever been done to ensure any kind of balance – much entertainment value can be found in just watching the overpowered broken characters go to town.
I hope Card Sagas Wars still gets released one day; it's a MUGEN derivative, but considerable care seems to be going into it.
In the meantime, why not take a look at Skullgirls? Everyone seems to appreciate that one.