I just swapped my cases from the huge Corsair Air540 and I'll just tell you. I'm the worst person to ask about the small form factor lol. These are just a lot smaller than the 540s. And that with enough space for cable management and, above all, for fans. Even my 540, which appears to be 3x the size of this case, I could fit a maximum of 7 fans: the O11 holds 9. It's also made for water cooling, which I did on my last case. While this one had even more room for ideas, this one does in a much cleaner and smaller form factor. Which I especially like because I'm using a full size ATX board. It's a bit wider than most regular towers, but that's a big minus for me. Aside from having to get a new SFX/SFX L power supply which is harder to find, this was a great purchase for me.
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