Just reading some of your posts I wonder about the Mac Mini.
What software you use to use it?
Intel mini running Tiger and
ATV4Mac software
How you connect it to the TV video input? What is the screen resolution you get and response time?
DVI to HDMI cable purchased at Amazon for less than $5. Previously used an Apple DVI to RCA converter on my old TV. Both ways need to fiddle with the resolution as it often gets wonky when switching between

TV and the Mac UI. Best method is via
SwitchRes X which can selectively enable/disable certain resolutions and keep specific apps from changing the resolution on their own. I've set mine to run at 1360x768 on my 720p TV.
Sometimes the response time is a little laggy. From what I've read that may not really be a function of running the ATV4Mac software on the mini, the actual

TV interface is often sluggish.
What remote control you use?
Apple Remote, the original Intel Mac minis came with one, not 100% sure they do anymore. There is an updated version of ATV4Mac that works with the iPhone Remote app, but this with update iTunes syncing is broken, which defeats the whole purpose. So I've stuck with the older version and the little white guy.
How you browse the web from your couch?
Can be done within

TV software plugins with just the little white remote (very klunky). I have a wireless keyboard to use with Safari and other Mac apps when not

TV-ing. However I've come to the conclusion that web browsing is simply not meant to be a "from the couch" experience. With some internet-savvy sanctioned plugins (think widgets or iPhone apps), the

TV
could be useful to snatch some quick tidbits of info, but traditional web browsing just doesn't work from the couch for me.
Sometimes it seems 2 instances of ATV4Mac end up being launched, while you are watching one video, you can hear another in the background. Backing out of the video and selecting it again usually fixes it. Haven't figured that one out yet. Sometimes ATV4Mac won't launch at all after using the underlying Mac, and computer needs restarted to get it launched again.
Even with SwitchResX installed, every so often the resolution gets whacked, or no picture is displayed on the TV at all. Usually unplugging and replugging the HDMI from the back of the TV will fix it, but every so often I have to go back into the SwitchRes control panel and reset the resolution, occasionally even requires a restart before it "sticks".
The WAF is very high as long as the

TV interface is up and running, which by and large is the case. But when it gets sluggish or occasionally crashes back to the Mac desktop, the WAF dips below zero as I pull out the wireless keyboard and "troubleshoot" to get it back to the menu.
Cannot access the Apple Store directly from ATV4Mac any longer, I think the store requires a higher

TV software version than I have, and I am not updating as described above. However content purchased from iTMS on computer and synced over works fine, including rentals.