20-40 materials is (to use a technical term) fuck all - You have nothing to worry about. Assuming you're in Ue4 look at the stat console commands to see draw calls/frame times etc. Don't get too hung up on it though, if you've done a village with 20-40 materials you're probably doing it right
ok thanks for the replies. I think in general the scene is using maybe 20-40 materials total on screen at any given time (with props). Ill have to do some profiling, something I havent done before. Ill look up some docs on it. Thanks guys