DD(5) has worn glasses since she was 2. She has had 3 trips to WDW and 1 to DL since she has been wearing glasses and she has used the transition glasses on each trip. They work great for her. You don't have to worry about keeping up with 2 pair of glasses. She has not complained of any problems with them changing back too slow when she has gone inside places at WDW. She does have the lighter lenses. The only issues we have had with them is 1) if you take pictures with outside characters, your child will have sunglasses on in the pictures- it isn't like you can take them off like you can with regular sunglasses (unless you have no glasses in the pictures) and 2) they will not transition to dark when she is riding in the car- they stay as regular lenses. All in all, we really like the transitions for any kind of outdoor activity. I don't remember how much they were, but I know they weren't cheap.
Oh, I should add that when we were considering them, we were told that today's transitional lenses were nothing like the ones they had even a few years ago, and that they were much improved now in terms of changing back more quickly, not being too dark etc.
