They shipped within 5 days of their schedule given to me, and notified me of the delay. I think the entire order took about one month from when I placed it to when I got it. I have read the horror stories about KMA on the net as well, but my experience was quite positive and above board. They did forget to weld my tow rings on, but the shipped them out as soon as I notified them of the error, and then refunded the cost for the welding job done by my local shop to put them on.
As a comparison, I attempted to order a front bumper from Road Armor, and was given a ship date about 6 weeks from my time of order. After 5 MONTHS of waiting, and an absolutely maddening lack of good communication from the company, I cancelled my order and got my money back.
Only thing I think that Kennesaw could improve on would be finishing, as the bumper still had sharp edges on many parts ( paint doesnt stick well, giving rust an "in" ) and they don't pre-drill the mounting holes. Went through 4 drill bits doing it myself, someone with more patience and the right equipment may not have run through as many. The sharp edges I took care of myself with my angle grinder, no big deal. So far, the bumper has held up just great, and the bumper is on rock solid.
The Nissan Frontier build-up on the home page here uses a KMA rear bumper as well, slightly different design from mine.