I didn't even know this existed, and I was a huge R&C fan back in the PS2 days.

I played the demo and it screams co-op. Do-able in single player but not all that much fun. It's good as a one time level in a full Ratchet and Clank game but I don't see myself playing this repeatedly.

$20 feels a bit steep for this. Maybe the levels in the full game are a lot bigger, the demo one felt tiny with little to do. It all looks a bit boring too. You can complete it in 5 minutes if you didn't have to run back to base all the time to repel another wave. But I guess that's the gameplay. Run out, unlock a weapon, which triggers an attack wave, repeat. Get enough weapons, attack enemy base. Collect enough bolts to buy defenses before pressing a button to start the final wave.

6 is about right based on the demo. After all 4 one it feels like another step back from all that makes R&C great. Although there is one redeeming factor over all 4 one, you can at least move the camera again.

I'm hoping Insomniac are holding back the next proper R&C game for PS4. If the franchise carries mainline games over to PS4 then this will be the first Sony exclusive franchise to straddle 3 generations won't it?

I think I'll skip this game, it'll be the first R&C title I don't own.

Twisted Metal, WipEout, Gran Turismo.

First one without vehicles to straddle 3 generations, sure.  Sly Cooper & God of War will also reach this milestone, though.