If you want the sound card merely for REW and don’t specifically need some feature that the M-audio and E-MU offer, you might consider the Tascam US-122L. It’s quite a bit cheaper than those other two you’re looking at.
Here’s a thread where the M-Audio was used successfully – not sure what the OS was, however.
What you might do is Google “m-audio mobile pre reviews” etc. and see what you can find on these cards. Often people will mention what their OS is in their comments.