I was cruising through the tower of latria level of Demon's Souls when I got ambushed by a mind flayer. I had not had any problems w/ them before that point but the damn camera wouldn't lock on and I missed my attack and he smoked my ass.
My ONLY complaints about Demon's Souls involve the camera. Locking on enemies can be tricky in certain situations, and general camera functionality in tight corridors or around pillars just blows.
Locking on is a major grippe for me, as a few of my deaths have been because for some reason I can't lock on.
Other wise this game is a major treat. Probably in my top 10 of all time.