I’m using KZ AS10 with Comply Foam tips and I’m more than satisfied! The noise rejection is so high that I can’t play without signal on my IEM channels because I can’t hear my drums anymore. Cymbals are totally gone, drums almost. Marshalls do not exist anymore… I use them for IEM in the studio and during practice with my Rockband and I can tell you: we are not silent! The only reason for custom moles for me would be the better comfort if wearing the IEMs for hours.