It's worth having those initial lessons to get your left hand position sorted out. As you get better, it gets harder and harder to unlearn bad habits, and an awkward left hand grip that works ok at the elementary stage can become a very real pain as you develop.
I also agree that unless you want to learn classical, don't bother with a nylon guitar, as the extra stretch for the wider neck more than compensates for the advantage of the lower fretting force.