Just started the Ratchet Collection and almost fully through with the first one. So far, I have to give the edge to Jak. Ratchet has gorgeous environments, and maybe it's just this first installment, but the gunplay is more frustrating than fun. Without a reliable lock on system (and enemies frequently not being on the same plane as you), it's a pain trying to use the better weapons without wasting ammo.
Jak's a mixed boat though. You have the beautiful yet simple Jak1, the wildly inconsistent difficulty of 2 (matched by a dramatic change in the story's tone), and a very well-rounded Jak 3. All in all, I found them immensely enjoyable and couldn't wait to start the next one.
The only Sly I had fun playing was Sly 1. Everything after that was mini-game tedium and quickly turned into a chore. I have never been happy to be done with a game as Sly 2 and 3. That said, Sly 1 was a lot of fun. Probably because it resembles those old-school platformers I love so much.
What happened to survival horror? Ironically, it did not survive - TheCyborgNinja