I went with the Windows version and installed it on a spare PC I have lying around. 3 megabits of bandwidth (or thereabouts) so I have no problems in that department. Streaming from Netflix it is just as you predicted... somewhere between SD and dish HD... not great, but definitely a good way to get a video without waiting on the USPS! My wife is THRILLED, as she could care less about PQ but is addicted to movies and to Netflix.
I'll try to get her into Hulu, as well.