I have this case, but you can even use a PSU that has an 12 cm fan since the case has holes on the bottom to suck in the air. The PSU would function as good as in a normal ATX case. But getting a PSU with the fan in the rear would allow the heat coming from HD to be pushed out the back of the case better.
But I don,t see how the case could be incompatible with modular PSU, and have not rread anything about that when I did some research on the case.
I have that Lian Li PC-V1000 and just bought a new psu for my new quad core system. The PSU is from Tagan (700W!) and it wont work straight away. The fan is just under the Aluminium which seperates the PSU area from the MB area. If you turn it around (sucking air from below) then you wont be able to put the psu inside at all because all teh cables push against that aluminium which seperates the PSU area from the HDD area.
Now I put the psu only half in and half of it stays outside. Not nice but at the moment working. I will get some aluminium scissor and cut a hole of the aluminium plate which seperates the PSU from Mainboard. This also helps cooling the mainboard area and VGA.
I have the Lian-Li PC-V1100 Plus II, and a Corsair 650TX fit like a champ, but I am currently using up 3 of my 6 harddrive bays for cable storage. Not a big deal since I don't plan yet to ever have more than 2 or 3 drives, but it is what it is.