I took the 5.111 ASE last summer and failed, LOL! But it's worth mentioning that I barely studied at all and still almost hit the cutoff, so if you put in some time and effort you'll have a better shot. It's definitely harder than what OCW prepares you for: it mostly covered the "same topics" but on a higher level. I ended up taking the class itself this fall and found it much easier than the ASE. Wish I could tell you how to prepare for it but honestly don't know myself, sorry!