I've had a pair of Park Avenues for the last five years. They've been my go-to for funerals, black tie, job interviews -- I even got married in 'em. Then in January I ordered a pair of black Carlyles with a Dainite sole, since I'm in a tuxedo often and sometimes the weather is nasty.
For me it's no contest. The Carlyle is a much sleeker shoe in every way; I'm happy to lose the captoe if it means my feet look that much better otherwise. If I wore a suit to work every day I could see the utility in having two different pairs of black balmorals, but as it is the Park Aves are now more or less relegated to the back of my closet.
I am on day 1 of these Carlyles, but so far I have to say I sort of agree.