Buzz, I've been welding for 30+ years and there isn't much I couldn't do with a TIG torch to a gun that needs to be done, and/or should be done. I really could not explain the technical differences but I don't see the need for what seems to be very expensive equipment that is more suited to a very specific operation. I don't think I would seek out a laser welder to do a job because there is some great benefit. How much colder can it be and does that really matter? How small do you need the weld to be? I could weld a hook with a deposit of less that .060" and not loose and edges to undercut. you could file all of that off in less than 10 minutes. So would it really matter if it was only half that much. An experienced TIG welder can do what ever you need. But maybe I am just an old dog that isn't learning any new tricks. Just my two cents.
Bill G.