I suppose it depends on what radio you use. I am not familiar with Futaba, I use Spektrum DX7. The Radio system costs $349.

If done separately or as a 'pack', the RX costs 99 bucks. Servo's cost about 30 bucks each, depending on what ones you get, and I typically use 5 servo's, although the throttle servo is usually a standard torque servo.. nothing fancy needed for the throttle. Now, for a more capable plane, high-torque servo's are probably gonna be needed for aileron, rudder, and elevator, and those can cost upwards of 60 bucks each, depending on what one you choose. Of course, there are cheaper servo's, for instance, a standard BB servo from Airtronics cost about 19 bucks each as I imagine do the Futaba servos and other manufacturers. But, the ones that come wth the DX7 are high quality, high torque servo's and they cost about 33 bucks each, which is a good price...And, you don't have to have a DX7 to use them, they will work on any of the 'big three' systems (Futaba, JR, and Airtronics. Hitec also, I think, and perhaps even Tower's radio). Sorry, I didn't mean for this to be an advertisement, I wanted to just offer several options.

The battery pack (s) plural.. because I use two per airplane, cost about 20 bucks or so each, so I also need two switches, about 5 bucks each, and one voltwatch which is about 20 bucks. You can do the math, but after all is said and done, you spend a lot on the electronics.

But, yes, the main reason is not to have seven transmitters and seven different systems to set up. It's a simple matter with the Spektrum to setup, say model #3 for plane #3, and so on.. it has a 20 model memory.