If you do, please have her practice applying it without bubbles. And get rid of the nails. It looked quite amateurish, and her not really being able to hold it didn't help.
It should definitely be shown off as a feature - everyone has had that frustration when trying to put a screen protector on some device.
Also, they say it can be re-applied. So maybe demo putting it on one way and then moving it to another wall or flipping it the other way. And demo on a non-white surface. It looks kinda transparent in the video because it's being stuck on a white background.
Also, if you stick with the same girl (which I think is totally fine), you should have her wear a more professional outfit (not to sound sexist or anything). What's your biggest potential market? (offices i'm guessing?) You should have her match that - so for offices, maybe business slacks and a professional top. Right now she looks like a college student, which is fine if you're trying to cater for that market.