it's hard to find a hobby quality trainer with that budget. you are going to be limited to proprietary electronics similar to the one you linked, which are made of stuff that you'll likely throw away instead of reuse as you progress in to the hobby.

it's ok to start with a "toy airplane", but remember that when you do get in to it, you're going to end up getting a 9c radio or better anyways. if you stick with electrics, you're going to end up with a collection of lipos and some fance charging equipment too. if it's nitro you go to later on, you'll end up with some high end os motors instead. bottom line is, be aware that getting in to the hobby can be more affordable by going for the gold and buying equipment that will do what an rc addict needs it to do.

if proprietary is the route you want to start with, you should check out walmart & target's selection of airhog rtfs. i know they look cheezy, but for $30 they'll be probably as much fun as the decathalon. have fun with it and get familiar with airplane stuff, like airpeed, stalls, approaches... all the while saving for a 9c and to kick off a more fruitful rc aircraft (&/or heli) experience.