H.W.
I would definately stick with the regular if he loves it since he'll eat it. Have you tried the unsweetened? Definately an aquired taste! It is also good if you put a little apple sauce or sliced bananas on toast. and they are getting 2 of the foods. Remember too to use only white bread and white rice. Not as healthy, but way easier to digest so that's all the DR's recommened for the BRAT diet.
Good luck!