Pros: Unbeatable sound.
Cons: Extremely flimsy design.
Do you listen to hip-hop, techno, etc. and other popular music of today? Are you frustrated with the lack of clarity/details across the board and the ridiculously loose and undefined bass in those "made-for-bass" cans (e.g. Skullcandy)? Are you equally frustrated with the shockingly lack of bass(especially if you don't use a dedicated amp) and the unbearably sibilant sound of those "high-end" cans that audiophiles seem to love (e.g. Sony V6)? Well, at least sound-wise, the RP-22X is exactly what the doctor ordered.
As far as sound quality vs. price goes, this pair is practically unbeatable for those who demand great sound and listens primarily to music with strong base(i.e. music from this century). I'm not great at describing sound, I just know good sound when I hear it. As far as listening to modern music goes in the $100 and less range, nothing beats this pair of cans' combination of tight, punchy bass and clear, expansive trebles. I've heard better bass and trebles before, but never both in the same pair and certainly not in this price range at least.
To summarize, you should get the Equation RP-22X if you:
1) Have high demands for sound quality but low tolerance for hassles like a portable amp
2) Listen to pop music of this century
3) Have the money for a pair of high-medium range priced headphones
You may wanna reconsider if you:
1) Think 1000W subwoofer with stock speakers sound amazing in your car
2) Use any classical or rock music to test the bass of a pair of headphones
4) Don't have the money/have too much money/don't care about sound