I'm fairly new to Jayson and Jay's videos, but from what I can tell they are good people. They do a lot of charity raffles, promote up and coming youtube pipe smokers, and promote various carvers. They are direct, unfiltered, and entertaining. You can tell that they are people with a passion for the hobby.
Like what delro said, they designed the pipes themselves. Jayson also inspects them himself before he ships it. He had a video where he was talking about going to the company and checking them out. He mentioned that they met his standards, and did have to take a few off because they didn't meet his criteria. I have read and watched reviews for the Dagner branded pipes, and have heard good things. For a machine made pipe, they are said to stand up on equal footing to both Peterson and Savinelli. The price is also competitive.
I think that many on this thread are coming off as pipe snobs based solely on the difference they have in personality from the Dagners. This is something I did not expect from this group of people. The Dagners do not seem like they are taking advantage of people. They sell merchandise because it's smart. When people like something, they like to show that they do. I for one would love a Dagner t-shirt and pipe. YouTube was something they did because they like the community. In my opinion, the branding of the pipe is no different from a tobacconist having a house pipe. That being said, like it or not the pipes are there and have been deemed decent and competitive by those that have purchased them. Let's be the community we are supposed to be, and not put down a pipe brother.