Summary: I bought these a few years ago on my first job. There is absolutely no sound leakage, the bass is strong which compromises a flat frequency response, but as as long as you're not comparing them back-to-back with high end headphones you wont notice (your ears adapt).
Summary: Wow i bought these in 2012. 2 years of abuse later they finally fail and fall silent. Failure was due to cable damage from repeated tugs/strains/getting caught in doors and on door handles. Using an Android phone with custom EQ along with.