I found a posting, in this thread I think, about putting the smallest size tip on upside-down or backwards, depending on your point of view, then using the more typical 5mm hole T400 size ear tips. For me the magic combination is the KZ large silicone tip carefully spread over the inner sheath of the inverted small supplied silicone. Size wise it appears to be the same as the supplied large silicone tip but the fit is much different. I get a good seal without fiddling and consistent solid bass without discomfort. Which I did not get with the supplied tip. Perhaps the double layer of silicone around the nozzle makes the KZ tip more rigid and that's why it fits better for me even though it seems to be the same size as the included tip.
So I'm enjoying these now. Perhaps I'll look into finding out how to get the Sony hybrid tips since I've seen them mentioned before.