I'm using 2 computers.
Evga x58 with asus dongle and Asus p5k with targus.
On p5k, with bluetooth wake option greyed out, I can wake my pc with apple wireless keyboard both Lion or Mountain Lion dp3 with update.
And after restart it keeps working.
On Evga x58, Lion 10.7.4 where wake option greyed out, I can't wake my pc,and also after restart keyboard does'nt work until os starts.
And if I want to choose hard disk on boot menu, I have to remove dongle and put it back again or have to plug out my pc and plug in again.
but mountain lion dp3 with update where wake option is available and I can wake my pc, and after restart I can use keyboard to choose hard disks.
On evga I don't have perfect dsdt. so when I shut down my pc , power led is still on. and also usb relate codes in dsdt are different between those two boards.
I think if you have good dsdt fix on your pc then even without bluetooth wake option, you can wake your pc with wireless keyboard or mouse.