Pros: The Noise Isolation is Like No Other
Cons: Some say the sounds isn't that great. I think it's good/great
When I go to a busy restaurant during lunch with my headphones, I feel like I'm by myself with the QC 15's. They work fine with your iPhone but if you get an Amp, you can change the setting on the headphone jack to Lo. Then, you can crank the Amp and you get some pretty good sound when you are at home. In my opinion, if you listen and get used to their sound, you'll be happy with the sound. Also, they fit well on my head, which I like. I felt like the other headphones (Parrot Zik, UE9000, UE6000 and others) moved around when I would walk. I don't recommend this, but they are GREAT to workout at the gym. I bring my iPad and can watch a TV show in a busy, noisy gym without having to crank it.
Don't get my wrong, you will hear sounds from the outside world, but they are sounds like someone talking or a siren. These headphones take out the background noise. Also, you can get these for under $200 used since they've been out for years. You won't get the Apple cord, but you can get that online. You will lose a little sound with the cord not from Bose, but it works and it's so nice to adjust volume, skip songs, etc.