I don't rightly mind which, so long as they are good quality shafts of the right spine to begin with.
I've had to go 23/64's on plenty of occasions to get the spine I need, but then I guess I've never really been a good enough shot to notice any difference.
For me they're both good, both sizes have shot brilliant, and put in the right place, with a good sharp broadhead, they'll both keep you very well fed....
Bare shaft, then a paper tune to double check and finalise things, and either is good to go.
Best
Lex