There are at least two Dish satellites at 61.5 right now: Echostar12 (formerly Rainbow 1) and Echostar 16. Service is being transferred from E12 to E16 rapidly, and when complete, E12 will go into storage as a spare.
Nobody posting on this thread is from Panama so we don't have first hand experience, I did setup a "C" band system in the Canal Zone for some DEA agents but that was a long time ago and completely different. To answer your question about best satellite you really need to find someone with Panama experience. That experience is probably not going to be found on this forum.
Because DISH is fine tuning a new satellite at the 61.5 location with more spotbeams a lot of the old information is no longer good information so it will take several weeks to adjust to the new limits and power of the new spotbeams.