I have done the headphone and IEM toss around game, and I'm back to where I started with full size cans. You can do the infamous upgrade-titus sickness that many of us have done and with withdrawals from time to time, or stick with a budget and call it good - for a while anyways. The PFE are great IEM in both price and performance and you can't go wrong with it or many other earphones in the same price range. You can also spend a little and get older top tier earphones like the SE530 and UE triple 10 for example, but again doesn't translate to better. After going through many earphones and cans, I've realized like so many others who have advised before, desktop applications (full size cans and amps) goes much further than a portable applications for the same dollar. Even though the top tier earphones sound great, when I step back and look at these small things and wonder is it worth $300-400, I get a little disappointed, but never at the Grados and Sennheisers cans.
Yeah, I did the portable amp/iPod thing as well. After buying/selling/trading I know longer own a portable amp and I'm content with my Cowon D2+ with FLAC and my Klipsch C3 which I just purchased again for the fifth damn time.
Sorry if I winded my reply. Good luck.