I don't, but know people who did and who love it. If you want to be able to do a variety of things, it is excellent. I would say it is a little more on the expensive side, and if you have never gone cargo before, you want to be sure you are really gonna use it. But it is definitely a candidate for replacing a car, even one that you can haul shit with.
*This is coming from someone with two cargo bikes at this point. I put 500 miles on my commuter (tern HSD) in the last 6 weeks, and use our Madsen with a bafang motor to do all of our local errands/kid pickups/etc.