It's all subjective but here's my opinion to take or leave...
Piano V3 sounds waaaay more real than V2. My favourite preset is the 1982 piano: finally, an Arturia piano that actually cuts through a mix. For me, none of the pianos in V1 or V2 were usable. The endless options of different piano types, lid positions, mic positions, reverbs and so on, never compensated for the fact they just didn't sound real. For my purposes, that made them pretty pointless.
Had I been Arturia, I wouldn't have bothered marketing a modelled piano VST until my programming team could come up with something that sounded as good as these V3 pianos. I only ended up with Piano V1 and then V2 via my purchases of the V Collections they came in. No way would I have bought them otherwise, because I felt we were being charged for the privilege of buying very-much-WIP software which really wasn't 'there' yet. But then again, Arturia would have lost sales by adopting that approach, which is probably why I don't work in marketing...
The V3 pianos are much, much better, and I would willingly buy the app for the upgrade price, were I not patiently waiting for Arturia to give me a good Black Friday deal on an upgrade to VC9, which will already include Piano V3.
