Any, in all the years I have dealt with Mobile Manufacturing, I have never had a problem. I know a couple people have had an issue or two, most of that was due to error in the correct oprdering of the part (s) and that was at both ends of the food chain, from what I have gathered.
I needed a single bolt a few days ago and it was in the mail to me in two days, as I did not order the item until late in the afternoon. I did find a bolt here on the farm that would work on a temp. basis. I could have run to town and probably gotten what I wanted, but by the time I would have done all of that it would have cost more than having it sent from the factory. Going into town taskes about 15 minutes and then to the correct store and all. I figured I would be almost an hour, plus fuel, so I found a temp and made the call. You also must know that I am only 85 miles from factory and about an hour and 45 minutes to drive.