The case SonicTransporter uses retails for a couplahundred. Passive, pre-built, NUCs, be it from Nimbus7 or from LogicSupply tend to be on the pricier side of things, you don’t get support from your friendly local dealer, and I tend to find 'em less pretty than Nucleus: direct, they’re about a grand, and LogicSupply is still on 6th generation if I’m not mistaken.
There IS a gap in the market for a really nice, diy buildable passive NUC case with space for an extra HDD, though (it’s of course subjective, but Akasa doesn’t qualify as “pretty”), and while my local dealers can die a slow, preferably painful death, I’d be happy to give RoonLabs HD-Plex ballpark money for one of their cases (and not bug 'em for support, and take responsibility for frying a CPU), but, alas…