There are really only two products in this hobby that I feel have been worth every penny spent.
PT (even though I bought when they were $50)
Spektrum
The reason I like them so much isn't because they gained me something in speed or performance but made racing that much more ENJOYABLE at the track. No more waiting for someone to return a transponder or waiting in tech to put one in, taking it out, etc. And the fact that I never go to a freq. board and can set trim/toe in pits whenever I choose makes racing more hassle free. Just my opinions.