I wonder what another good Vincent Price movie is... pretty sure he's in an earlier I Am Legend.
I was happy you liked that "Masque of the Red Death"...that one really stuck with me when I saw it as a kid. The other most memorable Vincent Price movie (aside from all his other bit-part roles) would be that "Theatre of Blood"...
http://en.wikipedia.org/wiki/Theatre_of_Blood
...catch it on Netflix sometime, if you like period horror movies. (Er, and if you are interested, maybe don't read the wiki page after all--too many spoilers.) :p It's over-the-top but engrossing LOL, just like a Vincent Price movie should be. :p