I think the arc midi would be a good project but you could certainly get a bigger case. This is how tigh it might get with a loop in it. It maybe worth considering getting a bigger case like the r4.
But is'nt the R4 the same size as the Arc only that it's sound isolated? The good thing I saw with the arc is that the Rad on top is mounted a bit of center so there is more roome above the mobo.
Oh sorry i thought the arc midi was a micro atx case. But considering thats the same size as an r4 maybe you might have to get a full tower to fit the loop inn without being so tight.
Budget is no problem, maybe nothing over $1000 (not worth it unless it comes with an Ice-cream and beer dispenser). But I still want to go for a commercial available case and not spring for a custom made.
I live 3 floors up and no elevator, so the few times I want to take the computer to a LAN I don't want to have to hire som movers just to get it down to the car. Thats why I want a normal midi or mini format.
I can skip on one of the Rads and only do one 280. Just getting a new case and not having a spot for the $200 rad I already own feels like a waste.