There is no issue with selling stickers and this is why:
You have to trust the person you get a physical bitcoin from, sticker or not. These things *cannot* be used as a regular currency or exchange mechanism, there will ALWAYS be a factor of trust required when transferring them, and there is no way to get around it. The utility of physical bitcoins is as a cold-storage wallet, and little else.
Anyhow, I'm redeeming mine and putting a sticker from a different company on it, because I don't trust Titan to hold the bitcoins, or anyone for that matter.
I agree that there is a factor of trust. At this point, I only need to trust one company - Titan.
If they sold stickers, then I would have to trust everyone else with regards to the face value of the coin.
Your choice to redeem your coin is yours to make. Why not post pictures and video on youtube so that people can see it being done.
I do wonder why you even bought a Titan if you don't trust them - Seems like a troll post to me.
I did notice you ignored the prior post about people making wallet coins in which they sell their own version of stickers so that you can seal anything you want. It's the perfect answer to your idea of what you're trying to accomplish.
Good luck with your project.