[Razor Ramon HG]

Depends what you need.

I don't recommend full-ATX cases any more unless you really like a specific chassis.. the NZXT S340 was more than enough to make me go from mITX to it. But I'm rocking a Clevo P650SE instead these days.

The only real difference is expansion slot and cooling.

Most mITX cases these days can generally fit most cards out on the market like the Corsair 250D. And even if they can't fit the regular full size version, manufacturers generally have ITX versions of certain NVIDIA cards like the GTX 970M at the expense of slightly higher temperatures.

And of course, smaller case equals less fans and more noise. A tiny case like the EVGA Hadron Air only has two exhausts, and that can affect temperatures (which is why it's recommended to use a reference style GPU with a blower fan to exhaust it out the back).

There aren't too many good mITX cases on the market that I can really recommend aside from the 250D (little on the larger side, but has great cooling and 240mm radiator support) and the nCase M1.

I find mATX to be the best compromise, but people downgrading strictly for size might not be satisfied enough. There are a lot of nice cases though without breaking the bank like the Coolermaster N200 and cases in the Fractal Design Core 1000 series.

Don't bother with the Bitfenix Pandora tho. It looks nice, but was a pain in the fucking ass to build in and made me want to smash it with a hammer.