We very much try to avoid them because of their unreliability. Standing on one leg seems to help the best but they are still very cumbersome and ugly. There are reliable alternatives at a higher price.

If you're just trying to penetrate a cabinet or you can run a wire to the extended location, the Xantech Xtra link kit works perfect - around $125. Speakercraft, Niles and Sonance also make a wired kit - these are not RF.

If money is less of an object, several remote controls will do both RF and hopefully simplify your AV system - Universal remote control MX-350 ($175?), 600 or the PC based 800 and 850 ($375). We mainly setup the 800 & 850. We generally get around 70 - 115 feet depending on what's in the walls.