The range depends on where its being used. kitchens tend to be very bad for bits (prolly has to be the two refrigertors here).
to increase range you can route the antenna on the car from the back of the board instead of the front (untie that knot as well). Even better is putting a 24gauge solid core antenna (cat5).
Now for the more exotic, remove the cripple cap on the car's PCB (be sure that's it before you clip it, don't wanna damage something you need), and remove the cripple cap i n the controller. just doing the controller and hte car cripple caps, i was getting 40ft+ in my apt (RF hell, cordless phones...yeah right...).
Also note that doing these mods can bug ya at races. I personally refuse to take un-capped controllers to events due to the sheer annoyance they can cause to others. Imagine trying to test a car, and sending some other guys car 50ft away right off the table
That's not cool at all. The car mod is a tamer mod but gives you an edge on the track since you have less chance of hitting a dead spot.
anyways 20ft is about ideal, good enough to be a slacker and run it from a chair, and not so far that the kid 50ft from you at the races will be able to shoot your off the table (well, unless he did hte controller mod...)
g