One additional word of advice before you pull the trigger. Make absolutely sure D* agrees you are out of contract. The least little thing can trigger another commitment, right or wrong. So get it in writing from a email or something so you have ammunition if they screw up your final bill. I had been out of contract for quite a while, and DirecTV hit me with about $800 in charges a month later, including ETF's and un-returned receivers. Turns out all were "errors" on D*'s part, but it took a lot of effort to straighten out after the fact. This is all in spite of the fact that they had previously told me over the phone that I was out of contract and my owned receivers were indeed owned. So make sure all your ducks are in a row.
I've come across a half dozen bugs on Hopper so far, but all are minor. Otherwise, it's a really good system, and I'm happy with it. Be aware that with 2 hoppers and 3 joeys, you'll have 6 total tuners, one or two less than you have now. So live tv can be more limited at times. And if you plan on using DLNA (Media Share), be sure to ask for a HIC (similar to D*'s cinema connection kit).
Good luck