If you don't use the ota input or if you have a separate cabling system, like I do for my own syatem and the high end custom installs, that I do a lot of, the best switch is the Zinwell SAM-4803 4x8 multiswitch.
It is small; It is weather resistant; it works with all DirecTV dish configurations (except those using two dishes); and it is reasonably priced at $50 from most suppliers.
I've got over 50 of them installed out there with absolutely no problems. Zinwell manufacturers a lot of units for others under their own labels. But, they have larger form factors.