Until recently I've been running MCE 2005 on Windows XP with Linksys Media Center Extender (MCX) connected to the XP box over 802.11a wireless network. That was a nice and stable setup, but with the technology moving forward it was time for an upgrade. I have successfully upgraded XP to Vista, and since Vista did not support "old" Media Center Extenders like the one I have, I had to get XBOX 360 - the only game in town when it comes to extenders supporting Windows Vista.
Cursory Google search revealed that even most basic and least expensive XBOX 360 version, the Core System, can run the extender application just fine by loading the MCX software from the Vista box over the network. Far more serious issue for me was how loud XBOX 360 is. The thing is that Media Center Extender box is located in the bedroom, and any fan noise from XBOX 360 would be very annoying. Linksys Media Center Extender was not just quiet - it was completely silent. It has no fans or motors at all. The price for the silence was that its CPU was underpowered and therefore it was mostly nothing but a dumb Remote Desktop terminal displaying the UI rendered on the XP box, with the exception of rendering the streaming media on the MCX box itself. XBOX 360 has a very powerful multi-core processor and therefore is easily fit to render all the fancy MCX UI right there, which makes UI of MCX running on XBOX 360 much more responsive compared the Linksys. The price of the performance, besides $300, is the fan and its noise. How much noise exactly? The whole reason I write this post is because after searching the "Internets" I was unable to tell whether the level of noise is acceptable or not. Some people complained that it's horrible, and some said it's OK. Well, here's the verdict: yes, the noise is bad and I can't believe Microsoft didn't find a solution to the noise problem, BUT the remedy is you can turn XBOX 360 completely off when you are not watching it! Noise level when you use the XBOX is not uncomfortable at all. The drawback is that it takes XBOX about 50 seconds to boot, load MCX application from the server, and launch the MCX UI when you turn the XBOX on (which BTW can all be done at once by pressing Mediacenter Green Button on the mediacenter remote). I don't mind paying the 50 second price for the complete silence of the turned off XBOX, while being able to enjoy fast and responsive UI of the XBOX setup.
Another quick note on the subject - the networking of the new extender. Linksys extender had both wireless and wired networking capabilities. I ran it over 802.11a (Wireless-A) network that is fast enough for streaming recoded TV and at the same time is not susceptible to interference from all the 2.4GHz devices like cordless phones and 802.11g (Wireless-G) networks of your neighbors. XBOX 360, however, has only wired networking capabilities, and since our house is not wired for Ethernet, I had to use ZyXel power line Ethernet adapter. I really like ZyXel power line adapters - they are great alternative to wiring your house or using wireless networks. When I was setting up extender piece on the Vista machine, MCE tested the network bandwidth and found the throughput not sufficient for streaming TV. I though it's strange because ZyXel PLA-100 adapter is supposed to be 85 marketing Mbit (about 45 real Mbit) - quite faster than 22 Mbit of the Wireless-A network that was working just fine. Sure enough, TV and video streaming ran absolutely smoothly over ZyXel PLA-100. However, whenever we get an HDTV set connected to the extender, we'll need to upgrade ZyXel adapters to speedier 200 marketing Mbit (hopefully about 100 real Mbit) PLA-400.
[June 12 UPDATE: The same day when I wrote this post I noticed that network performance of the setup has degraded to the point of recorded TV being unwatchable: picture would freeze or won't start playing back at all with the black screen, with "Network Issues" pop-up ever-present on the screen. I thought the problem is ZyXel PL-100. I replaced it with Viewsonic 802.11g access point connected to XBOX 360, and just like with PL-100 it worked flawlessly the first time I turned on the XBOX, but went down exactly the same way as the the power line adapter based network. Funny thing is that if I hit Fast Forward button on the MCE remote, FF works and produces absolutely smooth video! So at normal rate it crawls to the stop, but with fast forwarding there are no "Network Issues"? I was able to playback the same recorded shows over the same network connections using notebook and WIndows Media Player with no problems. I think Microsoft has a whole lot of explaining to do about its XBOX 360 "networking issues".