You've already gotten some good advice, but I'll throw my experience in as well.
If you play any other sims/racing games, a wheel may be worth it. I have the TX with the three pedal add on and shifter. It works brilliantly with Project Cars and Assetto Corsa... But Forza 6 is really shitty when it comes to force feedback and how it handles wheels. With lots of tinkering you can get it "ok" but it so far at least, isn't right or properly supported. When you hit bumps, puddles, when the suspension is loaded in bottoms or unloaded as you crest hills, when you come against curbs, etc... It doesn't behave at all like it should. When you have oversteer or understeer, it doesn't behave at all like it should. It's actually the opposite of what would happen a lot of the time and the experience is better with feedback turned off, which kills any and all reason to use a wheel.
It's a brilliant wheel for the other named sims however, and behaves properly and feels like you're actually driving the car. It is conducive to faster times in those, but far slower times in Forza due to the fact that you won't get proper feedback and have to counter everything it does in your mind with what it should be doing, and correct accordingly. They talked at one point about addressing the terrible FFB support in Forza 6, but so far seem to have not done so.
TL;DR - If the only racing game you play is Forza 6, and you play other types of games the rest of the time on your Xbox, I'd recommend the elite controller. If you play other racing sims as well, and don't play other types of games - the wheel isn't a bad investment. Mine gets a lot of use. Just not yet with Forza.