What brand? Before using it, I'd check on that first.
I used Herculiner. It has had different reviews from different people. Some people love it, some people are indifferent, and some people absolutely hate it.
Here's how I see it. Those that love it, either expected less of it, or prepared it extensively to get it right the first time.
Those who are indifferent got what they expected.
Those who hate it have never used it, have never seen it properly applied, or never properly applied it, so now it's coming off.
I for one Love mine. I've hauled a few cords of firewood (some uncut weighing a few hundred pounds a piece) and have not torn through mine, I have roughed up the surface, but not enough to warrant putting on another coat or anything like that.
Mine is old, it's faded, it's worn. I've never had had to patch any of it, I haven't used the UV protector for it, and haven't had any issues, except that I blocked off where the bed joins at the front, so water doesn't drain, I had to cut a bit away so it would when parked backwards in my driveway.
Tailgate where I taped it off.
Where the bed and tailgate meets.
My bed, those are mud stains from the last off roading trip (it easily loses it's luster if you don't buy the protectant, but the mud is easily removed with a brush, soap, and water.)
I've got more pics in my "how-to" on Norcal4x4forum.com
Prep is key!