I have a 2014 Silverado that just had the tsb done. The overall process was alright overall. I will say that I am alittle OCD about my vehicles so just throwing it out there lol. They did not hassle taking on the job at all which was nice, but I do have some complaints of the overall job done. They had the truck for I believe 3 total days. They did scrape off all of the wax coating and applied Norton rubberized undercoating to the whole frame. I do wish they removed the bed and rear bumper to do the job correctly in my opinion but they didn't. There are numerous spots of decent overspray which I am not happy about but the frame overall looks better than it was. Hope this kinda helps.... I will try to post some pictures at a later date.
-Mike