I like my moded Stax SR001 (see avatar) but they have no noise isolation and find them in that version the most comfortable headphones I know. With that ear mold they sit just above the ear channel and stay there quite securely. I also have Vsonic GR06 IEM but that are also not very good in loud environments. My ear channel on the right is quite narrow so I have problems with the fit of many IEMs. I tried HiFiman RE400 at the The Show last weekend in Irvine and they fitted ok if I am using medium/small tips left and right but they isolation seems to be not the best. A lot others I tested have to wide bodies to fit right.
I look for good sound quality using my AK120. I can accept some compromise in bass extension but can not tolerate too bright head phones. As they will be for limited use I do not want to spend a lot on them.