I know of Dave's Permanent Coatings (rvroof.com) and Rhino Lining's Eco-Coat. Both have had very good reviews. I'd stay away from no-name companies. They might just be spraying pickup truck bed liner on top which won't flex when the rig goes down the road, but crack, and cause very damaging leaks which are impossible to find. If it doesn't stretch and flex like the polyurethane epoxy compounds do, you don't want it.
I have no clue about the company the OP mentioned. They have a website, but neither yelp nor the local BBB have no reviews, either good or bad, so there isn't anything really to go on except their website.