If your cable company offers a 30-day trial period where you can cancel without obligation, give it a try.
Keep in mind that most cable companies offer inferior picture quality to Dish, many channels are analog and not digital, and the HD-DVR they give you may be sluggish at changing channels and prone to lock ups. This was the case with Charter in Rancho Cucamonga.
Keep in mind, too, that some cable content providers offer great picture quality and a very servicable HD-DVR. These carriers are, however, in the minority. The only way you can tell about yours is to try them out. Just don't cancel Dish until you are sure you're happy with cable.
If you just signed up with Dish for your 811 as a new customer, call them back and tell them you and your family decided you'd rather have the 942 lease and you goofed by getting the 811.
If you are an existing Dish customer, then they want you to buy a 942. A few have been successful at begging Dish for a 942 lease, others have not been successful.
If you have to buy a 942, I'd definitely check out the cable carrier in your area. If you like it you can come back to Dish as a new customer next spring and get whatever MPEG4 HD-DVR they have at that time on a new customer lease and get a deal on programming to boot.
Decisions, decisions......