Monster Hunter 3 Ultimate is an expansion of Monster Hunter Tri, Monster Hunter Portable 3rd, and Monster Hunter Tri G that includes all the Monsters from Tri and Portable 3rd (which is a psp game).
Monster Hunter Portable 3rd is kind of an expansion of Tri, as it has more monsters and includes the palette swaps of monsters for extra armor. Portable 3rd removes Swimming from Tri and many monsters that can only be fought swimming in Tri.
MH3U is to the "Tri" series that Freedom Unite was to the "Dos" series. It'll be the best version of all the Tri games because it will have the most content.
That said, I still prefer Freedom Unite because the Tri series is way too easy (I solo'd Portable 3rd on my own with only 2 weapon types, and for the most part with only 3 armor sets) and while gameplay is vastly improved overall (hitboxes, weapon attacks, more variation on monster behavior) Freedom Unite eclipses every other monster hunter game (except for Frontier) in content alone. Though that isn't fair, considering Freedom Unite builds from all the MH games that came before it while the MH3U series builds from the new monsters in Tri, the new monsters in Portable 3rd, and only about 8 monsters from the older games (Los, Ian, Blos, Tigrex, Narga, Plesioth, and maybe Akantor and Ukanlos)
tl;dr: So how does it compare to the psp monster hunter games? -less monsters than Freedom Unite --therefore less weapons than Freedom Unite --therefore less armors than Freedom Unite ---This is twofold. In Freedom Unite, higher ranked armors look different, while in the Tri Series they look the same no matter what rank -much easier than Freedom Unite -More weapon types than Freedom Unite -More weapon attacks than Freedom Unite -more "intelligent" monster attacks than Freedom Unite -more monsters over Portable 3rd --therefore more weapons than portable 3rd --therefore more armors than protable 3rd -more gameplay over portable 3rd (swimming)
It's actually really embarrassing how well Freedom Unite still stacks up to every monster hunter ever, but that's to be expected when you cobble a game together the way they did
Sorry there's just a few glaring issues in this that need correcting.
1. Monster Hunter 3 Ultimate is not an expansion of Tri G, it is the same exact game with some Japan exclusive event gear removed (like usual).
2. Ultimate does not include Tigrex, Akantor, or Ukanlos in the line-up.
3. G-rank armor in Ultimate does look different.
Anyway, now my opinion of how MH3U stands up against Unite. Well.. it just dominates it in every way possible. Much smoother gameplay, no more artificial difficulty (bad hitboxes, etc), switchaxe, monsters are funner to fight because they're "smarter," AND it just flat out looks better graphically.
The PSP games are harder for newbies to get into. If you're new, get MH3U.
And to the people complaining about the framerate, maybe on the WIIU version, the framerate fluctuated a bit, but the 3DS version had no random fps drops. Not one person on the 3DS boards has complained about it, and I've played the demo a LOT and haven't noticed any drops whatsoever.
The controls are fine, most of the people complaining about the controls used the claw on psp for a long time, and just can't/aren't willing to adapt to the virtual d-pad, or even the cpp because its "inferior".
Actually, you should probably ask this on the MH3U boards, because some people there actually HAVE the game (japanese version) and they'll tell you which one is better. The Vita board will just try to persuade you away from getting anything on the 3DS most of the time. --- 3DS: 0146-8850-9059 Steam: Tzuba
The AI is much smarter but they changed most of the hit boxes to compensate for the increased AI. New rathalos can kiss my felyne's butt though. --- Currently playing : Monster Hunter 3G , Metal Gear Rising ~PSN: AppleDough