In my experience trace antennas can't be expected to work over about 30 m, even outside. I'm surprised that Hallard found a set that worked to 50 m, but he can't remember where he bought them!
Antenna efficiency depends strongly on length, with the shortest optimal length being about 1/4 the wavelength (perpendicular to a 1/4 - 1/2 wavelength ground plane, if possible). Also, transmitting and receiving antennas must be oriented parallel for optimal range.