Due to various combinations of upgrades either clearing to BP or not clearing due to full flights (and being stuck in economy) I've yet to actually fly in a Spaceseat. I have however spent time with people sitting in PE while I've been in BP.

My personal preference would be for a D/E seat, mainly because I hate having to climb over people. The idea of the outer and middle seats being different was that the outer seats would be picked by individuals, and the inner for couples. I know quite a few people who fly regular in these who always pick D/E

Climbing over from a window seat isn't difficult, but can be if the person in the aisle is sleeping. Row 23 being a bulkhead does have quite a bit of extra legroom compared to the other seats.