I finished this game today, everything but the epilogue. It feels like a PS2 game throughout, and I enjoyed it. Some good character interactions, and while there is plenty of subtle and not-so-subtle humor there are also some surprisingly heavy themes at times. Compared to my memory of the previous games, I mean.
I’d wondered whether there might be any direct references to Irem games, and there is one (the so-called “fighter aircraft” compass).