I'm what you call a audiophile on a tight budget. I love getting nice treble, bass, highs, mids and lows without having to pay hundreds of dollars. I'm not saying that the high end stuff isn't worth it but it is simply not in my budget as a college student. I use Grado SR80i headphones w/ a PA2V2 at home and used to use Sennheiser CX-300's for music "on the go." My Sennheiser recently broke after 2 years (loose connection problem at the y-connector), which is why I purchased these.
Overall, I can definitely hear the improvement over the CX-300's. The difference is not dramatic but if you pay attention to sound quality, you will hear the difference. Every type of music I have listened to with these sound great (rock, jazz, trance, hip-hop). The build quality on these is far superior to the CX-300's (thicker cable, better reinforced y-connector, better reinforced 3.5mm connector (gold plated)). The cord is detachable from the monitors so if you ever damage the cord you can easily replace it without having to buy completely new earphones. I looked up the replacement cord on amazon and it costs $35 (on sale) which isn't bad... The cord length is more than sufficient (64").
At first I found putting on the earphones a little awkward since they are not the traditional styled earphones but I got the hang of it within 5 minutes or so. I use the default synthetic (foam-like?) ear-bud attachments. The medium foam-like attachment fits my ear very snugly and are very comfortable. I can see my self wearing these for hours without any problems. Finally the noise isolation is pretty good (significantly better than my CX-300's silicone). Fitting is very important for these earphones quality sound + noise isolation. Small, medium and large silicone AND foam attachments are included.
The pouch that is included is helpful BUT I wish they had included something to help with wire management. ie. something to "wrap around" and place the monitors inside, instead of just a sleeve. I usually just wrap the wire around my finger and carefully place it in the pouch and zip it up.
Overall I highly recommend these for the price. $100 well spent!
5/5