[quote name='Darrcyphfeid']No. The amount of content actually in the story mode, without all of the repeated bits and general fluff, would only be on par with maybe one dungeon/month of scenes when compared directly with Persona 4. Also, the game's title is a bit misleading; Persona 4's cast is obviously present, but the game acts as a general fanservice extension for players old and new.
No idea how relevant it is, but also bear in mind that even the PS3 version will only work on an NTSC console. It's the first (and only?) region-locked game.[/QUOTE]
Whether it's worth $35 is up to each individual, but every Persona 3 or 4 fan should pick it up eventually. Definitely fun to see these two teams interact and actually does a good amount to flesh out the P3/4 world.
It will probably drop to $20 in a couple months, although I'd encourage people to support such a niche title.