These headphones are great. I listen to mostly metal and have listened to Grado's mostly because of it, and these phones are really similar to the grado sound; I can see why people refer to these as the equivalent to a closed grado headphone. It's funny to me how different these phones are to the description of every other sennheiser headphones. Every review for the hd 600 or 650 talks about their laid back nature, while the hd 25's are anything but laid back. indeed, they are very forward, and for metal and rock, this is just what the doctor ordered. Bass-y music sounds great too, these headphones can really bring out the lower end of the sound spectrum. My only gripe with them is the initial comfort - it takes a bit to get used to the amount of pressure they put on the ears. After owning them for over 3 weeks now though I can say that I love this set. While its hard to argue with the portability of IEMs, these guys just sound so good I am willing to give up a little more space in my backpack when i need to store them.
 
Highly recommended, especially with the velour pads!

When my 3rd set of Bose noise-canceling ear buds broke, I decided to look into a different type of headphone. The first site I stumbled upon was CNET, and for a couple of hours I poured over their headphone reviews. I eventually decided on the Grado SR60i because of their low price and the high regard that everyone held for them. I drove to the nearest audio store knowing which pair I was going to purchase, however I also tried a couple other Grado models that were on display (mostly the 80 and 225). In all honesty, aside from the sound difference over-ear headphones provide, I couldn't really tell a difference from the ear buds I had been using for years and years. Despite my initial reaction, I still bought the 60's, and headed home.
My first listen with my new 60's was even more of a let down as I realized just how much the sound leaked. With my girlfriend across the room, I couldn't turn the volume up beyond 2 or 3 levels on my Macbook Pro. I was dismayed; not only was the sound not mind blowing, but I had to be in a room alone to be able to listen to the phones at a reasonable volume. Instead of giving up on the Grados however, I again ignored my initial reaction and kept the phones. 
Let me fast forward to June 21. I was sitting on my couch after work, zoning out on the internet, with my Grados on and my itunes blaring away. By this time, the 60's were more comfortable, but I had still yet to fall in love with the sound they produced. Then, all of a sudden,it happened: The song Hold My Finger by Sikth came on, and I had to stop reading whatever I was skimming on the internets because of what was going on in my ears. As the guitars switched back and forth between the left and right side and the bass noodled in the background and the cymbals crashed, I realized that I could hear it all, and not only could I hear everything but it was clear and warm and bright and a million other descriptions.
I have no idea if this sudden epiphany of sound was the result of burning the phones in, or of my ears getting used to the open-on-ear design, or what, but whatever the case, I definitely love these headphones now. People on this site and others love to use hyperbole to describe certain headphones, and I think I am getting a little bit closer to speaking hyperbolically about these 60s.
Despite the leaking sound, these headphones are the s*** (in a good way). Oh, and I also found out that they are easily modded...as if I needed another reason to like them!
 
Also, on a side and closing note, Sikth is an incredible band and really showcases the ability of these headphones, check em out if you have any affinity for rock that dabbles in metal and weirdness.

These in-ear buds come with apple products. Everyone uses them. Not much to explain, really. They are not very high quality and hurt my ear after wearing for a few minutes. Only pro besides that they are free is that I have them when my other IEM or earbuds break