[mythtv-users] Favorite low noise/low power frontend solutions (MediaMVP v. X-Box v. other?)

[Jeff]

I've seen people recommend X-Boxen and  MediaMVPs as "cheap" frontend
solutions. We currently use an old Pentium box which we keep turned
off most of the time because its noisy.
It would be nice to replace it with something else. We're also looking
for a 2nd frontend so we can relocate the current backend+frontend box
to the basement where its cooler (help the disk drives live longer). I
think low power & low noise are probably the two biggest requirements
for a frontend in our house. I don't think we need a 300W power supply
for a frontend box.

Are the X-Box/MediaMVPs pretty much interchangeable in terms of
features/mythtv support? Any gottcha's to look out for with these?
Specific models/revisions which work/don't work? Other favorite
frontend solutions? So far the only caeat I've seen is that you need
to keep the files as mpeg2 for the MVP. Same for XBox?