With the Mac-Mini, you toss in the Apple OS CD/DVD and it installs and you get to use the machine.
With the Shuttle you'll likely spend the first month installing and configuring Windows.
Bob
In regards to the Mac Mini vs. the Shuttle XPC I 8600b:
Personally, I found the comparison a bit unfair, not to mention unequal. (Whats the point of comparing a PC-only system to a full system?). Granted, the Mac Mini is a nice piece of work (its sleek; I'll give it that), but what was the logic in regards to their choice for Shuttle? I mean, why compare a $500 PC-only Mac Mini to a $1100 PC+LCD Monitor+keyboard combo?
Though I've not worked with Shuttle's XPC systems, their barebone systems are very good (not to mention fairly quiet, which is impressive given the graphics cards and CPUs some of them can handle)
I'd probably have compared it to a Shuttle SN95G5 stocked with similar parts (40 gb HD, 256 RAM, Video Card, etc). The cost would've been much closer.

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