You may get a 24, you may also get a 20-23. All will do the job, the 24 is simply the fastest of the bunch. (there are some differences in HD sizes between the models, and the 20 is the only one with built in OTA tuners, the others use an add on). Functionally they are all the same though.
I am with Directv now and got the HR24NC-100. It is a pretty nice receiver and seems to run cooler than the VIP 722 that I had with Dish.
