Does this have a funny taste to it?

A little yes, it's like a mint kind of, a good representative is the Floride the dentist paints on your teeth but with mint. It's not that bad and I was surprised on how well it sticks ... You can eat normal foods and for the most part the product stays on.I highly recommend this if you want you're teeth to look disgusting lol!

Can this be used on implants or a bridge?

Yes, I didn't experience any problem applying and removing this product to any of my teeth--including crowns. I utilized vodka on a cotton pad to remove the material at the end of shows and followed that with brushing my teeth with my regular toothpaste.

Is anyone else having trouble opening up the black tooth fx? I now have a blister on my finger from trying to open this, it’s like it is glued on.

I didn't have any trouble; however, your bottle might have been sealed with some of the product near the lid. Perhaps try running it under hot water or using a silicone pad as a grip. I hope your finger feels better!