Well, 150m sounds pretty darn good, :-). I tried the little nRF2401+ modules a couple of
weeks ago, and got only about 10m range [1 mW, 2.4Ghz] - disappointing.
I am also wanting longer range for my largish 4WD robot, which is intended to go off
across fields the size of baseball pitches, etc, so 150m sounds great. As the robot will
actually be "autonomous", for fail-safe, I plan to have the base station continually
pinging the robot, and if the signal drops out, then the robot will backtrack along its
previous outgoing path until it's back in range.