[chrisjw]

Good point, yes should have said! Only using it from an iPod Classic / iPhone so no DAC needed with Westone 3 ears.
 
Agree I keep reading conflicting messages. I like the E6's size but the E11 isn't that much more expensive and if it's significantly better quality then I'll put up with the extra size.
 
Just read the Music On A Budget: Sub $100 Portable Amps Shootout review and as i'm a bit of a bass head then the E11 starts to appeal more.
 
Can see me buying both, trying them and selling one...

 

[Anathallo]

E7 > E11 only if you need the DAC.  The amp-only E11 sounds much better than the E7 in my opinion.  The digital volume on the E7 + E9 compatibility is nice, though.
 
Never heard the E5/E6.

 

[gamersince1976]

I've heard (used to own) the E5, and currently own both the E7 and E11. The amp in the E11 is much better than both the E5 (which was anemic and caused a lot of background hissing) and the E7 (which I now only use with the laptop for the DAC).
 
As I understand it, the E6 is an update of the E5 - and, while an improvement over it's predecessor, still isn't in the same league as the E11.
 
I think the E11 is a good amp for under $100, and I've heard really good things about JDS Labs CMOY as well. Either would be a good option.
 
However, if you're looking for something for $100 down (in some sort of layaway program, perhaps?) might I suggest the RSA SR-71A Blackbird, which is what I just did myself.