Depending on your budget for the project, consider making the flat bed a dumper as well, very handy.
Mine is steel bed and headache rack, with braces to hold 2x8's as side boards, 2x4's in the stake pockets, and so far has held up to some log hauling abuse pretty well. The stakes are going to be replaced by steel though, for log hauling.
The bottom is a diamond plate texture, better than smooth surface in my mind.
It dumps too, a pto off the tranny, factory setup, and quite handy. You could always go with an electric-over-hydraulic if you have an automatic.