I have already beaten it and am starting my new game plus.
The game is fantastic. You never stop gawking at how visually stunning the game is. While the 30 fps feels a bit sluggish for long-time fans of the series, you get used to it after about thirty minutes.
It's also laugh-out-loud funny. Some of the jokes are Portal-level funny. There are plenty of shout-outs, like the cheat that turns bolts into rupees or the fact that the Warmonger turned into the Peacemaker (Jak and Daxter reference).
I really only had two problems. The first is that there was a lack of a gladiator arena which was one of my favorite elements. The second was that the game felt the tiniest bit too... Uncharted-y. From the cinematic camera angles to the yellow-painted cliffs, there were times when I felt like I was playing Uncharted rather than Ratchet and Clank.







