There should not be any difference depending on single/dual conversion. But some receivers are "short range".

But in practice the transmitters differ a lot. Some people are satisfied with 30 meters with collapsed antenna, but me (and my buddies) who use Multiplex and Graupner always have 80 meters or better. And on the bigger planes we walk a complete circle with engine running at this distance.

Some state that the plane should not stand on the ground but 1 metre above.