I'm the one setting up the ramdrive and had originally hoped to use ramdrive.sys. The Unix guys got a little glassy-eyed about it until I told them not to worry -- it just looks like another disk to their code. The whole ramdrive thing was a step into the wayback machine for me. I haven't used one since my BASIC/MS-DOS days. I'm using RamDisk and so far it seems to be working.
Well. If they have difficulty with DLLs (SOs on linux) then kernel level drivers will slay them. The randrive.sys driver is no longer available in windows 7 (hope they weren't thinking of using it ) but there are a few 3rd party solutions I think.
One final thought. Turn off the nagle algo. It is known to play hell with things like games and it is known to silently introduce delays in packet sending through the loopback. It is off for my setups for this very reason, although I never saw 2 second delays.
Disabling Nagle's algorithm is something I haven't tried yet, but only because it's supposed to be for optimizing small data packets, and 5MB isn't very small. But hey, I've tried everything else, I can try that, too.