I never got the discourse over POPs. I get it wasn't a Kojima baby, and so it's non-canon, but on the overall, it was a decent little time, and a nice way to bring something more MGS feeling to the handheld alongside the AC!D games(which are also excellent times once you grasp the card system).
Of course, I'm a little biased, Null was a huge hit to my edgy teen heart. I wanted some of the full-body panels as art on my walls, I was head over heels.