Headphones for New User? (I have Beats by Dre). Looking for Techincal Help/suggestions.

So I got Beats studios about a year ago (and they broke). So I took them back and got credit for them and upgraded to the Pros for about 100$. I had been looking at all sorts of reviews and everything said the Pros sounded great. I bought these about a week ago and was enjoying them, then I continued reading reviews and stumbled onto head-fi. Everyone who reviewed them here seemed pretty adamant that for the money these headphones were no good.

What I want are headphones that sound great, but unfortunately I am just now getting into the technical side of the discussions on headphones. To date the Pros sound better than anything I have used and I have nothing to compare to when trying to get something better.

I use an ipod touch

I buy music from itunes

So I am looking for recommendations on something I can use for casual listening that will sound great. I'm hoping to sell these Pros on ebay and upgrade to something better, but I don't want to buy another headset for 300-500$ if my 4000 song collection of 250 kbps files will still sound ok.

This seems to be the place to go for advice on anything audio, so I am hoping for some good direction on what to buy with what I have. I want to be able to plug into my ipod and listen. As it stands now I don't have room to get another music player if the ipod is insufficient for higher end listening.

I was looking at Sennheiser 650s on ebay for 350$, which seemed great? I hear those run about 500, but I don't even know if I will hear anything different with my current library.

Thanks for taking the time to help me out.

I listen to Metal/Rock, a little Hip Hop and Techno (DnB).

I was just now reading a little about needing amps for higher end headphones since you mentioned that.

I do a lot of casual listening, and I have a tendency to carry my headphones pretty much everywhere with me.

As far as the sound goes I want heavy base, and clear guitar on the metal.

The main thing I need to know is if I can actually hear anything better than what I have now. 256 kbps out of an ipod. Is it even worth trying to upgrade?

Thanks for the reply. I have been spending the last few hours looking into different headphones at different prices.

I just put in an order for Shure SRH840 for 125$ and a  FiiO E1 to power it while I am not at home. I was reading that these are pretty flat (in comparison to what I'm used to anyway). I have a lot of music, and I was recently listening to a lot of bass heavy tracks because that's what sounded good on my headphones. No harm in getting something flat and taking another listen to everything on my playlist right?

I suppose the next step is to look into a cheap/used headphone amp and maybe start getting CDs instead of digital copies of my music.

Learning a *lot* from reading around on this website. Now I just need to get as much money back for these clunky pros as possible (I wouldn't worry too much about the headphones being heavy or uncomfortable, these Pros kill your ears after like 30 minutes, and weigh a ton). If anything sounds the same or better than it does right now I'll be very happy, considering that's a 270$ difference.

I get the feeling I will be lurking on this website a lot in the future. Thanks again.