Honestly, it depends, the EX-10 is great and works for just about anything well, but the XS3 comes with everything you need and is synthesized out of the box, and if you have raced before you know that not having that last frequency left is a big pain, for the MBX-5 I recommend the XS3 because of its RTR qualities, but if you race hardcore, then the EX-10 is your best bet because of its INCREDIBLE adjustability and servo speed (faster than HRS)