That is a good price you should be able to bind that Spektrum RX to one of their higher end transmitters when you want to. I have an older Futaba 3PJS that has been upgraded to 2.4GHZ. It works good for me. Your going to be bashing no sense getting a full blown race radio. The Losi is a solid chassis.The others are more for racing unless you plan on heading out to the track the 810 looks like a good buggy.
Here is one to look at.