I did a multiple dish set-up several years ago with a DRD420RE receiver, a 36" dish aimed at 101, and a 18" dish aimed at 119. I used a Hughes 2x1 multi-switch.
When I got ready to add the 110 bird for HD, I added another 18" dish with a sat C LNB. I still used the Hughes 2x1 multi-switch but with the sat C combiner going into the 119 sat input. The 36" dish was still used for 101.
3 separate dishes would probably get a better signal than the oval dish. I know my set-up did. You can also use a 4x4 multi-switch as mentioned above. I prefer the 2x1's as they seem to get better signal strength, although a 4x4 would be better for a mulitple receivers.