A quick Question?

Sure. You just have to factor in the constraint of space, which means you have to check dimensions of all your components. Also, you've gotta be pretty good at cabling, because there isn't much air to move around in those small boxes in the first place.

You just have to compensate for the size of the box with hand-picked parts and custom jobs at putting things together. Sometimes you may even be required to mod the chassis (cutting, re-routing, drilling, etc.) to make ends meet.