The wing T has strengths and weaknesses just like any offense. In my experience most teams don't run it correctly...they block like I teams and try to make the wing T work. If run correctly the wing T is very effective up the middle (trap, counter, belly-g) and off the corners (waggle, boot, buc-sweep). It is not so effective off tackle nor is it particularly good for drop-back passing.
All in all I think it is a fine high school offense...if the coach knows what the heck he is doing.