I'm sure you've read about the double-blinded tests (DBT) Harman did comparing P362 vs speakers costing several thousands like Martin Logan. And most people preferred the P362.
So unless it's a DBT where we can truly compare w/o bias (aesthetics, price, prestige, etc), there's really no telling if one is
much better or significantly better for more money.
If you paired the P363 w/ a sub from Ryhmik, SVS, HSU, Velodyne, Funk, Epik, RBH, etc, and compared to F12 or Q900 w/ NO subs in a DBT, I'm betting on the P363 for any music with good bass.
For example, you went to Fry's and bought P362 for $200/PR. Then bought HSU VTF-2 MK4 for $519. Or Rythmik FV12 for $550 when available.
In a DBT, I'm not sure if another pair of $2K speakers (w/o subs) would sound better if your music involves good bass.