I own the FiiO E7/E9 combo and it is more than capable of driving 80 ohms. I have a set of 300 ohm MB Quart QP400 cans and even those get too loud when I turn up the E9 to just halfway.
I personally haven't had the best luck with the combo though...the connection between the two devices is really messy and not very secure. Twice now I have had one of the connection "teeth" break and the device started only playing out of one channel. For a cheap, entry level amp though it is a great product. My roommate has the combo as well and he has had no trouble whatsoever, so I may have just recieved a faulty device. You won't find an amp for $120 that has the raw power of E9 anywhere else.