The comparison of this combo to MDMA was made by the dude who ran Chemical Resale of Santa Barbara, one of the first (maybe the first? i forget...) places to sell these and other research chemicals. So basically, it was just an advertising ploy, they feel NOTHING like MDMA. Never underestimate the power of placebo though, you give people amphetamines and tell them they're barbs and they get sleepy, you give someone BZP/TFMPP and tell 'em it's like E and they agree, thats just how it goes.
In my experience, BZP isn't half bad for hte price, kinda feels like dexedrine just with a bit more nausea/hangover.
TFMPP on the other hand was absolute shit, horrible stuff, I wouldn't bother with it.