I second on all of the Project Rainfall games, I never got a chance to play any of theme are they're going for ridiculous prices these days. Although I hear Xenoblade is really the only one worth playing.
I missed out on Xenoblade too, not paying that price either. But, having played The Last Story and Pandora's Tower,
I'll say The Last Story is definitely worth it. Pandora's Tower isn't and has a game-freezing glitch you have to work around in the NA version :/ but The Last Story is definetly worth it. If we get Shulk I think we should get Zael too, but I suspect both will be trophies.
Seriously, The Last Story is glorious.