follow up to my original post: I've got my um56 adaptor tips back for the um3x, and thats just about the shizz. I loved my ety ER-6s behind a dark tube amp, but these can sit behind just about anything close to neutral and be happy. The comply tips that are stock suck, but the um56 tips which are molded are nice.
It seams they recommend the vinyl ones, but I'd almost be tempted to get the ottoblast tips next time. I have one musicians plug done in ottoblast from them (reshelled), and it's slightly more comfortable but probably isn't as accurate.
All told, it's like $500 (inc impressions, phones, and tips), but I'm rather happy with them.