Will it last forever.no but by then my son probably won't be obsessed with captain underpants anyway. It was well priced and fits my 3 year old son fine. He is more the size of a 5 year old though wearing 5t clothes 47 lbs and close to 4 ft tall.
Pros
It was for my dog............ part of his "Underdog" costume
Cons
The cape may be too flashy for some kids to wear in public