I didn't start really listening to a lot of stuff until high school. Before then I used some old, broken (held together by duct tape) open air sonys that cost about $10. I actually remember them sounding quite good as I ended up breaking them completely, which caused me to have to use some old Koss cheapies, which were terrible. I've been looking for a new pair of those Old Sonys I used...just out of curiosity.
Anyway, after I used those really cheap koss, I realized that I actually really cared about sound quality, so I moved to some more expensive koss earbuds that had the cone shaped foam fittings. They were really nice...but they broke.
After getting a very small taste of better sound with the koss earbuds, I began to save money for some V600s I saw in radio shack...not knowing any better of course. I eventually bought these and I freaked out...I thought the sounded incredible. I used these for a very long time (also getting some somewhat inexpensive sony noise cancelling phones and getting the MDR V150 for portable use). Thinking I was at the best level I'd get sound wise, I got a pair of Bose on ears for christmas. While I now dislike these phones because they are really muddy and bass heavy, they were much better than the V600 and the others I had been using.
I eventually started reading about the Sony V6s, which I still use to this day. I bought those and...well that's about as high I have gotten sound wise. I'm pretty content with them though. They are very good.
Incidentally, I've also added the koss porta pro, JVC flats, and the Bose around ear headphones to that collection. I used to have some nice philips phones that were around $50, but I gave those to my father for a gift.
Incidentally, the bose around ear phones correct the problems with the on ears-not nearly as muddy and the bass isn't ridiculously overpowered.
But as of now I use mostly my V6s and my Bose around ear. I think my spending spree is mostly over...I may eventually get a really nice pair of sennheiser some day. But I'm very content with both of these headphones. They both reveal a ton of detail that I never got with my younger days of listening, and they are both very well made and comfortable. The bose are incredibly comfortable and I love the warm sound, although it can royally annoy me sometimes. I think they'd actually be better than the V6s if they had less sound coloration.