Here's a look at the inside of the 380t
http://www.techpowerup.com/201683/co...itx-cases.html
card length is supposed to be upto 290mm space and cooling shouldn't be any major issue, however it is on the large side for an mini-itx case
450mm tall, 365mm wide and 440mm long
Although it does come with a built in handle for easier transport.
On the 780 SC ACX & Hadron Air . . . hard to say, probably not but maybe, if it does then it'll be very tight fit, best bet would be to contact evga and ask them.
on the msi nightblade, it is a bare bone system, ie case+psu+motherboard but at £375 that is still a bit pricey, the motherboard is the MSI Z87I Gaming AC I think, which is £130ish, the psu is a Silverstone ST60F-ESG which is another £70ish
So £175 for the case . . . yes that's over priced.
For low cost have a look at the Coolermaster Elite 130
The Silverstone SG07 or SG08 is still worth a look
Also the corsair 250d, a bit on the large side
Coolermaster HAF 915 R & F versions might be worth a look too.