Anyways: I've been thinking about building an mITX home server/NAS for a while, and have been thinking about combining it in the same case as my main rig.
Does anyone have any experience with such a project, or any warnings they might share? Similarly, posting some dual-rig options would be swell, as I've discovered they're a little hard to search for!
I have a Fractal Core 2500 and a Fractal Core 1300, not a single case solution but similar to your plans. They will get their own trolley in the future so they can be easily moved for cleaning. I've chosen the Fractal Cores because they looked similar to each other and were not overly expensive.
Thing to come are: trolley with soft wheels for floor protection, some sort of cable management solution, a switch and some storage. Not quite sure yet how it is going to look.
you can get the Cooler Master HAF Stacker cases. there is an ATX case. (which is the primary case) and then they have an ITX case which goes directly under the ATX case or on top of it. It's meant for Water Cooling but this would be fairly neat for you. you wouldn't need that table anymore.
I have not found any reason to complain about them. They are the lesser brethren of Fractals bigger cases (like the R5) meaning that stuff is sometimes riveted and not screwed but for your basic: 1 GPU, single Processor and couple of harddrives system they should be enough. They have a mounting option for dual 120 or 140 radiators which cannot be covered up, so that is not something you want for a system with loud components.
Although I have to correct myself: I have the 1500 and the 3500. Both together will cost around 110 pounds. Could be cool if you build a trolley thingy, could also look and work terribly. But it will be cheaper than the dual cases. And there is no harm in going through several iterations of the project with improving DIY skills.
Oooooooooooh it looks great. This review is pretty informative (power supply placement issues - https://www.youtube.com/watch?v=0CEB71nZRPQ) but that's a hell of a case. Cheers dude!