If you are racing where they require a stock spec profile for 17.5 (no electronic timing boots) then right now the most hassle free is going to be the LRP SXX V2 since you do not need to use a booster or a receiver battery pack to power the receiver. I think Speed Passion also has one out that doesn't need a booster or RX pack but I'm not sure on that. And soon the Viper Vtrax1 will be released and that one also will not need a booster or RX pack. If your club allows electronic timing your probably going to want the Tekin RS.