1 - Sorry - ANY scenario for you to add either the 721 or a 501/508 will call for replacing your current LNBF (I'm assuming all other IRD's you have are still active). The DP34 switch will only work with the DishPro TWIN - a totally different beast than the one you currently have. If it was me, I'd replace your Legacy TWIN with a Legacy QUAD LNB and pull the extra 1 or 2 cables to the 50x/721 new location. Don't forget that the 721 will need 2 cables to use both tuners.
2- Correct - get it hooked up, then call Dish to activate.
3 - I don't have one, but what I'm reading on the boards is that the 721 is MUCH better than the 501 was when it was released. There are still a few niggling little things, but it mostly works.
2- Correct - get it hooked up, then call Dish to activate.
3 - I don't have one, but what I'm reading on the boards is that the 721 is MUCH better than the 501 was when it was released. There are still a few niggling little things, but it mostly works.