ultra hold is waterproof and very strong. I believe the perfector glue is a white glue that is water RESISTANT but not water PROOF. I don't know much more about the perfector glue than it's been around a very long time....not sure why people are just now trying it, BA tried it years ago and said it was about like any other white glue. But as with any adhesive glue or tape...they all work differently based on ones body chemistry.
DebbieS.