The tips they supplied are as good as it gets-- I have weird ears that fit certain tips much better than others. In terms of fit I think it's to do with all the drivers and tech that they have in the IEM. In terms of fit, VE is mostly a CIEM company that is more recently branched out into UIEMs. With EXT it seems like they were trying to get the best of a custom & universal fit.
Boutique IEMs push boundaries with sound signatures , driver configurations and shell designs-- there will necessarily be tradeoffs with universality in fit & appeal...but for some/many of us it's worth the risk for the quality of sound and overall we get. Even Sony, the most mainstream brand there is, when they attempted to push boundaries and give it their all they came up with the IER Z1R, an IEM notorious for the fact that it's hit or miss with fit with many people.
