I started with a set of E2's.... and loved them. Moved up to the E3C's when they came out and I won't turn back (tried Etomyc's and others but they just didn't cut it for me).
I would like to have a set of E5's, but just can't get to the $400 difference in price from the E3's. The improvement in sound isn't with quite that much to me.
D.