Pros: Fun, fun, fun. Ideal for jogging/bicycling, brilliant highs and more detail thn you could reasonably ask for for at the pricepoint. Did I mention fun?
Cons: A design only a mother could love, pinchy earclips, flimsy cable, not bass-focussed, leaks too much sound for public listening at volume..
As someone who enjoys all different kinds of headphones and has owned a few different ones at a number of pricepoints, I can reccommend only one headphone to pretty much anyone who listens to music and wants more fun out of their portable rig. That phone is the Koss KSC75.
Why are these phones so great, so much so that I am on my fourth pair? For half the price of an apple earbud, you get a pair of detailed, easy-to-drive, energetic and involving headphones that will bring out detail and life you have never experienced with the phones that came with your ipod/iphone/walkman/discman/minidisc player etc. While they are not perfect, They are so good that I use them more than any other phone I own (including ones that cost 100 times more) that I can only assume that it is my favourite headphone of all time.
Looks aren't that great, let's be honest. You aren't going to impress your Dr. Dre Beats-wearing friends with these, and the clips take a while to loosen up to where they dont pich your ears. And don't expect world-class build quality either -- the plug and cable is flimsy and is prone to breaking easily. It helps to be handy with the soldering iron if you want em to last longer than the gestation period of your average foetus. But that's not the point of these beauties. It's their incredible sound quality for the price means you can buy three or four pairs and always have a spare ready in case one needs repair or needs to be tossed.
In terms of genres, I find they do best with genres that aren't so dense and layered. Metal and heavy rock can get a bit muddled and muddy, but it's still a marked improvement over most earbuds. Jazz, folk, country and blues go fantastically well with the Kosses, and electronica sounds great (but a little light on boom in the bass area if that's your thing). Hip hop is not my area but the stuff I have is serviceable but not outstanding. I should mention that they don't isolate sound at all, which is both a positive and a negative. For me, it means I can use them while riding my bicycle at low volumes and still hear quite a lot of what is going on around me. For that reason they are the only phones I use on the bike or when running. Not that I necessarily endorse using headphones on a bicycle, though I have done it extensively for many years and am still here to tell the tale. So there's that. Of course the negative to this is that they leak sound like crazy, so you have to have them pretty low not to annoy people on the train or in the office. This is their mean weakness in being a portable phone, so if you listen a lot to music in public, you might need to look elsewhere.
They respond well to amping, I use a Ray Samuels Hornet portable headphone amplifier with them and they do gain a bit in bass control and punch, but the beauty of these phones is that you can drive them perfectly out of your iphone or ipod headphone jack. They give great detail but they're not so good that they make your 128kbps rips sound like crud, which is a big issue with the better phones. And their all-plastic construction means they're light and very portable.
I love these things and I hope they never go out of production. They can be modified and repaired easily, are cheap as hell and worth at least five times their asking price sound-wise (but not construction wise). Try a pair today, you really have nothing to lose, and I guarantee you'll like them a lot more than your apple ibuds. You might even like them more than your $1000 Beyers or Sennheisers