Worth noting, not sure what you can do as a retailer, but CS agents at Dish, when upgrading a customer's system, cannot choose what receiver of the 622/722/722k series the customer gets. I know some folks claim I have no clue whatsoever about this, maybe a retailer has been able to do so, but a Dish phone rep simply cannot do so. I had to deal with a recent escalated issue where a customer had to have their old 301 replaced, and it was replaced with a shiny new 211Z that does not have a coax output or interactive features. Some agent had tried to set up yet ANOTHER upgrade for the customer (with the hope they'd get a 211k), and the problem is this...if the tech only has 211Z available as a HD solo, running another truck for the same thing is going to result in yet another disappointment for the customer.
Point is, while the odds are very, very high a customer would indeed get a 722k (or perhaps a 722) if they did a Change Receiver on the 622, it's not guaranteed. If the 622 was bad, and getting RA'd, the odds are high they'd get yet another 622 (Dish does try to do same-same on RA receivers). But the upgrade...well, most likely a 722/722K, but I don't know that I'd go into a 24 month agreement for one.
Somebody with a 622/211 is going to see a $12 increase if they go to 1 Hopper/2 Joey. DVR fee changes from $7 to $12 (+$5) and they will have two $7/mo Joey fees as opposed to the single HD solo fee they seem now. (+$7).