I'd go to the Consumers Reports or Stereo Review web sites and see results of the testers' evaluations.  Check out the big box store like Costco, Sam's Club, Best Buy or Circuit City to see what's on sale.  My Recoton phones have a range of fifty feet but I have never tried to see how the signal made it through walls into another room though if within specified range that should be no problem in theory.  I haven't used my wireless headphones in years.

Peace and love,

Flakey