You should ask around at your flying club field, and see what the opinions of your soon to be fellow fliers are. This goes for the radio and engine. As for the quality of engines, this is my opinion:
Jett
Os Fx (not LA)
Enya
Irvine
Super Tigre
Thunder Tiger
The prices are comensurate with Quality, buy as much as can you afford. Get at least a .46 so it will be useful in your first sport plane.
Radios are all about the same, buy whatever most of the trainers at your field are using, that way when they help you learn to fly, they are experienced with it, and may have buddy boxes you can use.