The fiio E3 and E5 might be worth getting, but I've read over time they can start causing hissing. I'm trying to spend no more than $20-$30 on it. The reason I'm looking for an amp is that I've heard the HD-201 are not very easy to drive. I'm mainly going to use the headphones for...

I placed a bid on a PA2V2. I'm having second thoughts though, should I forget the PA2V2 and get another amp (possibly a CMoy)? I'm gonna be using this amp from an iPod LOD and they will be powering a pair of ATH-M50s.