In my installation, I have a massive tree that prevents my 110/119 dish from spotting 129, which also prevents spotting 110 from where I *can* spot 129. What I *really* want are three Winegard 76cm dishes, each peaked on it's own bird, feeding into a DP44 switch.
Unfortunately, the 129 dish is mounted on the roof, and I'd rather not strain it with anything bigger than a 24" unit.
I'm no pro, but I think that most of the D500 installations have LNBFs with internal switches, just for cases like mine (and hers). The problem with the 1000.2/1000+ systems is that in reality, the three birds are not on the same skew plane. If you peak the dish for 110/119, you lose a little on 129. If you peak for 119/129, you lose a little on 110. A 1000.2 system may be good enough for most people, but in your situation, it's about as easy to "wing it," if you'll pardon the pun.
I just wish that Dish could figure out a way to balance the channel selection on two satellites instead of forcing everybody into complex three-bird configurations. Wish in one hand, want in the other...