Paul,
You have to take into consideration the fact that in the USA they have this +ve and -ve shift issue. JR Transmitters will never talk to Futaba receivers and vice versa, several other manufacturers have chosen "sides" (for want of a better word) and some manufacturers have receivers that have selectable shifts.
Martin,
Further to the above, there is a wealth of info on this site regarding shift and who supplies what, just have a quick browse or even use the search facility.
