I really appreciate the responses here. Thank you much.
Iceberg, DirectTV told us local channels will be available here in June. I guess that doesn't necessarily mean Dish will have them, does it? If Dish knows they are coming very soon I imagine they would go ahead with the SuperDish.
SimpleSimon, you're point is well taken. It is my thought also that the installer would not likely make an issue of the 4th TV, considering my situation; a little kindness most always goes a long way.
JD#2, my electronics man was here today hooking up a new TV to the home entertainment system, and he agrees if the RF output is 10dB we should be able to split to 3 TV's, though just barely. For the extra $5, though, the 2 dual tuners sounds like a deal to me.
I'm going ahead with the Dish order and let the technicians worry about the installation. My biggest issue may be the dish location. The new one's azimuth is 217, which, if the dish is placed where the old one is, will point directly into a nice size crape myrtle! All the other available locations on the back side of the house likewise will have, now or soon, tree interference, unless the dish is mounted much higher toward the peak of the roof. Our roofs here in southern Louisiana are very steep, and I wouldn't ask anyone to risk their life working up there. With all the modern technology we have how come those birds can't see through a few tree branches!?
Thanks again to all for your advice. If you can think of anything else I should consider, feel free to share it.