I've been putting in some time with my PS Classic recently.
It's funny... I'm still not a PS1 fan. The library of games is large, but most of them really didn't appeal to me very much. Worse, most games on the system have aged extremely poorly regarding both design and technology. However, it really only takes one or two games you want to play to make the whole thing justified.
For me, X-Com: Terror From the Deep was that game. It's easily accessible on PC, but (at least for me) slightly less convenient to play that way than to have a plug-and-play version available anywhere. Throw in Castlevania and Mega Man Legends, and suddenly this little mini console is actually something I'm getting a lot of joy from. It's also nice to get a few extra multiplayer games on the system - the arcade port of Bubble Bobble gets a lot of play, for example.
It's really a shame that Sony did such a half-ass job with this mini console. Underpowered hardware, poor user interface, questionable game selection, PAL version ROMs, not including dualshock controllers... it's like they were screaming "we don't care" when putting this thing together. However, replacing the games included on the console is easy, so I'm glad to have picked one up at deep clearance pricing.