The Fractal simply does not have a filter on the side fan slot which is the only thing that bugs me on that case. If someone could give me inside on dust entering from the side of the case or possibly adding a fan, that would be very helpful.
The Corsair 650D simply doesn't have an internal motherboard header for the 3.0 USB, which I'd like just in case. I could buy an adapter I suppose, but it'd be an extra hassle and extra cash.
I like more Corsair it have more External 5.25" Drive Bays. It have better cooling with 2x200 mm fans and 1x120mm fan. If you have an aftermarket cooler ,i don't know if you can put and use the side fan.