that's the exact reason I'm considering it, there are guys that are two or three years older than me and they aren't far along in the process, whatsoever... Ideally, one would be making more money, sooner. And in the early 20s the biggest asset is time.
Alright man, you could potentially save a few months of your life for the cost of whatever a PPL will run you in your area.
Then again the entire flight training process isn't by "class". Sure you start with a class but aside from academic phases like API and ground schools your progression is based on how the cookie crumbles. There are too many factors to list them all but they add up to a sprint and drift kind of situation. People you started before can and will pass you. Then later down the line you may pass them again.
That 3 or month head start you're trying to buy may well evaporate by the time you even sit down in primary because the TW you go to has a wait and the other didn't. Now people from your API class who went to the other finish primary before you even start.
And if you think you have a measure of control over factors like that, wait until you see the little day to day things that can build to significant delays or just the opposite can cause you to move through at a break neck pace. You have no control whatsoever over those.
Just go with the flow and study more than you think you need to.