What kind of drugs are you on? Supreme Clientele is in NO WAY slept on. And it is mentioned as a classic, and rightly so, all the time. It's more or less a consensus that it's one of the best "Wu" albums to ever come out, and most people who have even a passing knowledge of hip-hop rate it as one of the top-5 albums of the 2000's.

Unless you're using "slept on" ONLY in respect to the idiot masses who gobble up shit like BEP and Drake, then no, SC was in no way slept upon.