So I took my new-to-me Synchros out on a little bit of rock a few days ago. They are snug, as in my toes are crumpledf but my whole feets aren't smushed. I was a crappy climber before, and without the precision of a true slipper, and having my foot act as part of the shoe, I was skittering this way and that way, and climbing even worse than I usually do, if that is possible.
Ugh, I hope I get used to them. 60 feet is a long way to climb with your feet paddling all over the place.
On the other hand, if I have a better chance of being something less than crippled when I'm 60, it's all worth it!