What do I want?

I currently have 3 HR23 receivers which I was interested in upgrading to HR24 boxes because of a speed issue, where the remote becomes unresponsive and takes a long time to switch channels. I have seen others with the same problem, and I believe changing to the newer receiver will help, based on what I have read. The people at directv are telling me it will cost something per receiver plus they are saying I need to pay for a service call to plug them in??? My current receivers were put in about 3 years ago and I already have a modern dish and a swm. They are telling me I will get a much better deal if I let them upgrade to a whole-home setup. I assume they are going to swap an HR34 in, but what else? Will I have 2 HR23 receivers and one HR34? How will that work? Do I need to have an internet connection at one of the receivers? Or, at the splitter? It seems that if I have 2 HR23 boxes still in the system, I will have the same speed problem? I would like whatever help you can provide, because I feel like I'm at a big disadvantage talking to a sales rep who is pushing what he or she is told to push today, when I have no knowledge to make intelligent choices.