[mistertomlinson]

First off, how likely am I to need a refit? I can't imagine this being a frequent occurrence because I've watched videos of the custom IEM making process and it's pretty cut and dry. If your impressions are 100%, you send them in... they make a cast which is obviously the same as your impressions and they create the acrylic shell... again, it should be the same as your impressions. As long as you have a competent audiologist, I don't see where sizing could go wrong... yet I have read a lot of people here have required refits. I'm just worried I'll finally get my customs having waited so long, just to send them back for a refit.

Second question: is it a good idea to use these while working out or running? I can't tell you how many pair of earbuds I've ruined as I sweat a bit more than most people. I suppose the sweat gets into the buds and does damage the same as exposure to water. However, I was thinking with customs, seeing as how they are a perfect fit and reach further into your canal than traditional buds, I was wondering if it was even possible for sweat to make it's way into the openings. It would almost seem as though the IEMs would actually keep sweat out. I would certainly hate to ruin my first pair of customs so easily.

Thanks for any answers.