[mountaineer]

The depth doesn't matter. That would just move the focal point in or out. I would think the most inportant part would be the dish being able to be skewd. I have a small sony dish that works great for 1 sat at a time, it doesn't skew. If I strap a lnb on it to get both 110 and 119, I get very good quality on a clear day. That quality dropped fast with bad weather. I would say the 2 extra inches wouldn't help that much. If you can skew the 20 inch dish, it would be a good replacement in my opinion.