I'd go with a cacheflow box, myself. M$ ain't cuttin it.
We have about 1000 people pulling from two cacheflow boxes and they are very happy. Plus the cacheflow boxes take allot less administration. I mean with M$ it's *reboot* wait a few days *reboot* fix whatever broke while rebooting and of course to save changes *reboot*......and on and on and on..
