I would say that with a personal instructor you have a better chance of correcting bad habits, etc. Other than that, I find the lessons here much more worthwhile.

I had some work done on my old guitar yesterday and the shop offers lessons. They were asking $19 per half hour lesson, once a week. Not for nothing, but if I forget what was gone over during the week, I don't have the luxury of playing back a lesson for the umpteenth time like I do here.

I can even move ahead at my own pace here instead of waiting a week to maybe cover a new topic. How much time of that paid lesson is actually spent on playing the previous week's work? Doing the math, I would be out $80 before I, maybe, get through part of fundamentals one.