Has anyone ever used Judith August's Killer Cover or Joe Blacso products to cover their tattoos?

I'm dark skinned (think brown Filipina) and need a black tattoo covered up while on vacation with the parents. I went to a beauty store bc someone recommended Joe Blasco but they said that Killer Cover was better. I've read a few reviews of the product online but didn't commit to anything since i felt that they were just trying to make a sale. Has anyone used these products with success (tattoo'd covered completely). Was it waterproof?-- I'll be going in the water. Please let me know! Pictures would help also (link!) Thanks..