the sound isolation with the hesh is pretty good. if you put them on, then wait before you start your music, most low-decibel noises will be blocked out. and when you start your music, just about every noise disappears, and you can enjoy your music to the fullest
It has an excellent and clear sound. The sound isolation is perfect.
If you don't mind the tightness of them, which they are VERY tight on your head, which can be either very comfortable or VERY painful.
The Sound Isolation is the main focus of the Hesh Models, they are meant to be worn while snowboarding generally. They also have Virtual Surround embedded in them in the newest model, which Skullcandy doesn't advertise but believe me it is completely worth it. Don't buy used because they'll break. Lifetime Warranty is a plus though so you never have to worry.
Hope I helped.