I recently acquired a space invader board, and it is pretty fun. I would say that actuation force is slightly higher than blues, but they sound very similar. Mine is a tad quieter I believe. The click is a little more solid feeling than a blue, mainly because of the insane steel plate that they are mounted on in my case. After doing a usb mod, my keyboard has 5kro. Kind of weird I know, but on keyboard tests it can do ANY 5 keys, no matter which ones are pressed. I couldn't find any combination that allowed more or less.