For remote recording, the clean preamp + the clean compression and limiting = great for your 500 rack. Location guys will be very happy at least having the choice to access a pre (or line level from another pre) while on the road.
Voice over guys with 500 power supplies, another huge group of users that would absolutely dig both options but if anything, for the clean dynamics control.
The P1 is a different product, the P501 borrows the essential and most used features of the P1 and fits it nicely into a 500 rack.
Koed, I don't know if the P1 will enter into the cream colored arena anytime real soon but it's certainly not out of the question.
Stepwise Sound, thanks for the referral!
War