P90s tend to push the amp a little harder, causing some compression. For that reason, there is more touch-sensitivity in traditional Strat pickups than in P90s.
Yeah, I would suspect not since they're also wound hotter.
But they're still both vintage output pickups, honestly. If one can't get a very wide dynamic range out of traditionally wound P90's, it's very probably not the pickups' fault.
i think p90s are pretty dynamic overall. when you hit the string hard, you get strong output, but if you play more delicately, you can get some very sweet sounds as well
Also, the thing is if the amp is compressing from the hotter output of the pickup, then that doesn't necessarily mean the pickup itself is more compressed. It just means the amp doesn't have the headroom to handle them the way it's set. Easy fix just by dialing back the gain. Or volume if it's a clean amp/channel.
It can depend on a variety of things - there's so many wind and magnet combinations out there, vintage or new. A 5k A3 Strat pu is going to have a different feel to a QP! Same with an early 50s type P90 that's in the 7s with A3s compared to a later one that may be closer to 9k with A5s.