I installed a sidewinder and used it for three years/16,000 miles of towing with no problems. It is a simple, cost-effective way of ensuring that you have maximum turning capability while towing your 5ver with a short box truck.
I just traded for a long box truck and swapped over to a standard pin box setup. I was able to sell the Sidewinder for what I paid for it new.
I do agree that hitching up is a bit more of a challenge, due to the need to properly align the "key" with your hitch. Minor angle corrections can be made by simply moving the pin manually left or right, but only a few degees. In actual practice, I did not find this to be a problem.