I guess you could compare the C rating to nitro levels. Except when the lower nitro stuff stops being made. Original C ratings for LiPo batterries used in pattern were if I remember correctly, something like 6. They flew the models competitvely back then. You can't even buy them now.

Let's look at top line radios. Futaba 8GAP to 9ZAP to 14MZ. Each more capabilities, each more expensive.

JR Unlimited 8, PCM9, PCM10, 10S, 10X, 12X. Each more capabilities, each more expensive.

There have been medium range radios that have come out, ie. Futaba 10C, JR 9303, Airtronics SD-10, with the capabilities to use in pattern, and they have been lower cost. But almost all the winners in the upper classes use the top line radios.

Lets look at servos. JR 4000 series, to Super Servos, to current digitals. All greater performance, all more expensive then the last one. Same true of the Futaba line.

Now a look at engines. I started flying pattern with a K&B .61 engine. That was when 10cc was the limit. I then went to a ST G.60 BH, ST X.60, O.S. .60F-SR, .61F-SR, .61VF, .61VR, .61RF, .61 Hanno Special. They were all the same size and they were all more expensive then the previous. In 1.20's I went from the O.S. 1.20F to the Y.S. 1.20, 1.20AC, 1.20SC, all were the same size and more expensive. Then a size increase with the Y.S. 1.40FZ, 1.40L, 1.40DZ, all were more expensive then the previous, and they were all the same size. Hard to compare the cost increase with the 1.60DZ, 1.70DZ as they were larger motors. You can compare the 1.70DZ to the 1.70 DZ CDI. Same size, more power, more expense.

My prediction about electric systems goes something like this. There has been a reduction in prices in some areas of electric systems due to greater production as electric has begun to take significant market share from nitro. And as electric has opened up entirely new areas of the hobby, like the indoor arenas. This has been particularly true in the LiPo batteries. As market share stabilizes prices will do the same and then begin to rise in the upper end market as the technology matures and develops. The "sport" line of products, such as E-Flite, Rimfire and AXI will probably be pretty stable. I don't know for a fact, but I'll bet there hasn't been any price reductions in those line of motors since their introduction.