Just be careful when buying an 'owned' unit from ebay or craigslist. Get the receiver ID and call directv and verify with them that its an owned unit and not leased. About 90% of the 'owned' units people are selling are leased and they dont know it. When you try to activate it directv probably wont let you, if they do it'll count as a leased unit and you'll have to buy a new access card. The seller of the box will get charged the full price for the unit when they dont return it. You might also be responsible for any unpaid pay-per-views charged to the box.
Since the cost of a new owned HR box isnt that far off of the cost of the early termination fee, unless you're excited about owning a unit I'd suggest leasing with the contract extension.
As far as Uverse sucking, a lot of people in my area are having a lot of trouble with the installations. I havent heard many complaints about the service once its installed, but it seems the folks putting it in arent very experienced and its taking people 4-6 visits to get it working properly, and even then sometimes its not right.