I went to sign up for HD access today from DirecTV. I currently have a TIVO but it isn't HD. I was going to buy the DirecTV hd dvr but the CSR said that I could just as easily get one locally and wouldn't have to pay shipping. Is there anything special I should look for when I buy one? I also plan to buy a big TV so perhaps I can get a good deal with bundling. Do they all work well with DirecTV? Thank you.