The unit I have is a Tripp Lite SU3000XL. I looked it up on line, and they've change the packaging but the specs are the same. They run about $1100 or so. There is a 750 watt version (SU750XL) that runs around $380 or so. This would be great for running your whole media center.
In Trip-lite speak, this is an "online" style. Others call it a double-conversion since it takes AC and makes DC, then constantly takes the DC and makes AC (no relay to transfer the output). If you go to the Tripp Lite web site, "products -> UPS systems and batteries -> UPS by type ->On-Line" you can see all the offerings.
We had about 5 of the cheapie ("standby" type) UPSs and it was a pain to keep up with them and change the batteries. So when we built the new house, I ran dedicated outlets back to a small 6 position breaker panel and put the outlets in various rooms of the house where we'd have either computers or TVs. Now with the cheapie units down in the 50 to $100 range, what we did was not the cheapest but it's the easiest to maintain and it's a online type not the standby.
In the basement in the lower voltage wiring area, a 30 amp 120 circuit comes out in a twist lock receptacle. This is what the UPS plugs into/gets it's power from. There is a box on the wall with a dedicated wire coming out of it that has a 30 amp twist lock plug on it which plugs into the output of the UPS. That box connects to the small breaker panel box. Should the UPS fail or need work, I can just plug the 30 amp twist lock plug into the receptacle and everything works while the UPS is out of service.
It's not surprising that folks have had the whole house running on normal generators with no problems for 10-20 years. In general, all manners of devices are much better than they used to be at dealing with normal residential power problems. As far as the various electronic do-dads go, this is by and large due to the universal deployment of switching power supplies.
Due to the cost of failure, I hope posting "try it and see what happens" won't bite me if something has a problem. You should be good, lots of people have been good, but it's a try at your own risk situation. If we had more engineers than lawyers in this country, would I even have to say this

?
Pete