The bumper isn't held on by just those two piece of flat stock is it??
If it is, then I would highly recommend reinforcing it ESPECIALLY if that hitch is mounted only to the bumper as well. Personally, I think that is way too much weight for those 4 bolts to be carrying pulling wise (like on a tow strap), and as soon as you put a downward load on the hitch, that flat stock is going to bend like it is butter.
But, if that is a normal hitch/ is mounted like a normal hitch, then you are probably fine hitch-wise, but I would still recommend reinforcing the bumper more. It is better to over build, than to under build.
Now, enough with the criticism, I think it is an awesome looking bumper with the diamond plating. And the box fits in better being black.