I think it depends one what you want to do. If this is for a glow plane, then always buy dual conversion. It this is for an indoor electric plane. then buy dual conversion when you can. Some small electrics can’t handle the extra weight of a dual conversion receiver. There are some very small dual conversion receivers if your willing to pay the price.

A dual conversion receiver I believe cycles the signal twice to keep the glitches or hits on your channel to a minimum. They usually have a better range also. Again if this is for glow, always go dual conversion.

Max