[CABill]

If you want to REPLACE the 625 with an HD DVR, your cables can be used as they are now to the 625. But all you have gained is SD recording with more disk space. You didn't say what the TV connection on the diplexer connects to. The diplexer could be bringing an OTA antenna signal in to where the 625 is located, or it could be used to carry the 625's TV2 output back to the other room. If the former, you would gain OTA HD locals with a 921/942/622. If the latter, you would need some form of OTA antenna to get OTA digitals (HD).

If you want to subscribe to any HD channels from DISH, a 921/942 wouldn't do you any good. The advantage to the 622 is it can be used to subscribe to a DishHD package. You can't with a 921/942 - they are now OTA HD only except to someone that already had a subscription to the previous HD channel offerings. If you do want HD channels via satellite, you will also need an additional dish pointing to 61.5 or 129 and to replace the LNB you presently have on the Dish 500 with a DP Plus Twin LNB.

 

[CABill]

A 942 would be more value to me because I already subscribe to an older HD Pak & Voom channels (MPEG2 HD channels). You could split the antenna signal to feed both the TV and an HD DVR to record the OTA HD as well with any of the HD DVRs. The 622 lease deal comes with all the switches, cable, and labor to do the install for $199.

I assume that the 625 is the only receiver on your account now. It may or may not have a lease fee on your bill now. The 622 upgrade from DISH will produce a $6/month lease fee - even if it is the only receiver on the account. If you happen to subscribe to AEP now and were thinking of upgrading to HD Platinum ($15 increase), it might actually cost you the same each month to have both the 625 and 622 active on your account. Put the 622 where the 625 is (with its TV2 going to the Master bedroom?) and relocate the 625 in any other room (including the master). If you subscribe to some ATxxx package, keeping the 625 would add its $5.98 DVR fee each month.

As whatchel1 mentioned, there is a $10/month rebate for 10 months with a new subscription to a DishHD package that covers (over 10 months) half the cost of the $200 upgrade.