Everything which came after the inital UFC game on DC until UFC undisputed 2009 was mediocre or terrible.
The first UFC game on the DC was fantastic for its time, all the accolades from game reviewing websites and magazines prove that, it really was universally acclaimed.
UFC Tapout on Xbox was pretty much the same as the DC game, which was already like 2 years old, with a laughable Career Mode and exactly the same Gameplay without any enhancements.
Tapout 2 on Xbox was exactly the same shit, almost no new stuff and the same terrible "carrer mode" like from Tapout 1 and Throwdown.
The create a fighter mode was so bad, even the N64 Wrestling games, one of them being Virtual Pro Wrestling 2 (only in japan), had thousand times better charakter creation modes, and VPW2 even has a MMA mode, which for the times was pretty good and still is fun, and it also has a bunch of MMA fighters, like Sakuraba, Rickson Gracie, Bas Rutten, Enson Inoue, Don Frye, Funaki ect
Throwdown (PS2/NGC) was the same as Tapout 1 and 2, EXACTLY the same gameplay with virtually no improvements, and as i already mentioned it had the same shitty "career mode", and the same terrible CAF.
UFC Sudden Impact was the first game which had an somewhat ok Career Mode, but still nothing compared to the career mode from other genres, there was so much more possible. And it still had the exact same engine, almost nothing changed in those 4 years (since the dreamcast version).
No one wouldve said anything if they wouldve tried something new or if they at least wouldve vastly improved the engine, but it was the same engine, which was already 4 years old at that point, always the same modes, always a abysmal Career mode (beside Sudden impact, which still wasnt great at all though) and always a shitty CAF mode.
The controls were a travesty, the responsiveness was really bad.
I wont mention graphics, because thats not the most important thing for me, gameplay and variety comes always first.
And guess what, even the 2 Pride games on PS2 (Pride FC and Pride GP) have also the same engine, whereas Pride FC was ok thanks to its roster (but still the same shallow gameplay and engine + no career mode at all, not even a shitty one), Pride GP totally sucked. You instantly saw that its from the same developers as the UFC games (anchor).
The first good MMA game since UFC on DC (obviously for its time) was Undisputed 2009, which of course still had a lot to improve.
The 2010 Version was a bit better and had a good Career mode.
But Undisputed 3 is really still the best MMA game to date.
The only thing i still didnt like was the CAF mode (and still doesnt seem to be good in EA UFC), its really impossible to create authentic fighters who are not in the game. That really has to improve a lot.
I have not played EA UFC yet, but from what ive heard its mediocre at best.
EA