Fibre is stronger and lighter than clear scuff, it's why most pros use it.
I always find this interesting. 30cm of clear scuff weighs in at 3/8oz or 10 grams. 30cm of fibre scuff 1/4 oz or 6grams on my scales. So yes there is a difference, but it's absolutely minuscule in the grand scheme of things. If you feel you can notice that and feel it makes a difference, fair enough. I'm happy to put either on bats, or leave it off completely.
Is it stronger? Not sure as this is generally based on experiences, opinions etc rather than any specific evidence/findings and almost impossible to quantify. I've seen plenty of bats with fibre scuff which have cracked easily. My thoughts, if the willow isn't great, dry or has some defects like storm damage etc, then fibre or clear won't make much difference. I'm not sure how much difference it makes to stop damage anyway tbh. I generally recommended it to help offer some protection initially and feel it can help to protect the willow if people are playing against a damp ball.