I'm using Windows Server 2008 x64 R2 as a workstation OS on my laptop (8GB RAM). No issues. Bluetooth is not supported on that paltform but I don't really need it.
P.S. There is sort of an old movement on the web to turn Windows Server 2008 into a workstation OS. There are instructions on how to set it up for that scenario:
Convert your Windows Server 2008 to a Workstation!
Convert your Windows Server 2008 R2 to a Workstation!
P.S.#2. I have quite a long history of using server OSes on my personal machine:
First it was when Windows 95/98 was around. It had a nasty habit of freezing and crashing. One day it got on my nerves so I wiped it out and installed NT 4.0. First with 16MB RAM it was slow but then I upgraded to 32MB and it worked smoothly ever since.
Then it was XP which was good but still unstable. So I lived with 2003 Server on my machine for the time being.
Then came Vista. I installed it on my laptop and it just freaked me out. A colorful screen with many windows, all in bright colors, performance indexes, tools, toys, ads to upgrade to Ultimate. When I attempted to silence it all I quickly understood it would be a titan's work. It would have been too much for my nerves. So I wiped it out and installed Server 2008.
Then came Windows 7 but I didn't care to try any more...
In fact I've always lived with server OSes at home. Who's to blame if only server OSes from Microsoft qualify for a home workstation?