Overspray is not a problem according to the can. No negative affects on paint. And it seems to last forever, only needing to be sprayed when it gets stained again. what wears off is the shine, it will dull over time like armor all would. but this product doesn't leave any oily residue like armor oil, nor is it as shiny. when you spray it on, it evaporates withing seconds leaving it looking brand new, with no product left behind.
I use this on my BMW engine bay, which has a lot of black trim and black hoses. I seriously makes my engine bay look brand new. I have no idea how it works, as it isn't a cover up product, yet you only spray it on without wiping it off. and if you were to spray it on a cloth it's a clear liquid.
But what it did to my tonneau was amazing. I had the discolorations that wouldn't come off with soap and water, but Trim Shine did the trick.
If you do order the Trim Shine, I would get a can of their glass cleaner. Those are their 2 best products. The glass cleaner will clean any glass the first time, with no streaking ever.