Why not get a Dragon Link?
http://www.terranova.net/~winger/RCV...ite/DragonLink
Here is a google spreadsheet that shows comparisons of the Long Range Systems (LRS):
https://spreadsheets0.google.com/ccc...Aw&hl=en#gid=0
Ibelieve there is a pretty long wait for the dragon link though, but 25 kilometers would indeed be nice.