Being a happy owner of Parasound A23 and NC 2125, I second Parasound. Their solid and agil bass in particular attracts me to move from Cambridge Azur 851A to Parasound. However, I do agree with one of the comments that why do you limit yourself to these two brands while you have up to $4k to spend. I value Parasound gives the most bang for my buck but that is primarily because I have limited budget. For you, I won't say the sky is the limit but you do have plenty of room to work with.
Parasound A21+ vs Adcom GFA-585se
I want to change my amps from Wyred4sound SX-1000 mono blocks to a good class A/B amp. I was thinking of the A21+, but i looked at the 585se and the Adcom compares, on paper, to the Parasound JC5. Both have plenty of power to drive my speakers and cost the same. Anyone with experience with both?