Not me, but a caveat that the bumper is good for little more than storing the sewer hose (and I don't even use mine for that!).
To add a hitch of any sort, you need to have it welded of securely bolted to the frame. Even then- you need to check directly with Columbus and/or your frame's manufacturer to see how you'll effect your warranty by welding to it.
Most states will consider this double towing- is it legal in your state and the states that you'll be towing thru? Out east here, it's generally disallowed. Out west, you have to watch that you don't exceed length maximums.
And, of course, is your truck beefy enough for the extra weight and stopping demands? Will you have brakes back on that trailer?
And, yet another.. how will you see it to monitor it's all ok?
I'm not saying don't do it- just go into it eyes wide open.