The guy who installed these is not a welder by any sense of the word. I've had total rookies run a bead first time better than what I'm looking at. I welded for 49 years. Oilfield, offshore, shipyards, job shops, power plants, construction, industrial, pipe, tubes, water towers, everything from airplanes to artificial legs to gorilla zoo cages. It doesn't take a lot of weld to hold plenty of weight, but other factors to consider or the strength and penetration of where the weld starts and stops. If that is a weak area, it can cause even a good weld to eventually fail, such as leaving a crack in a crater at the end of a weld. I can't even tell where most of these welds start or stop. You can't tell much at all except the machine was set too cold and a lot of ugly stuff was ground off. They need to be ground out and welded over. As for powder coating, it's hard to tell from the photos but it seems there are a lot of flaws in that paint job for it to be powder coated. You must have done a flat or semigloss black. I also owned a powder coating outfit with a huge oven and never did a job that looked that bad from the pics. I could be wrong on that but it would be hard for me to trust a guy who would have a "Welder" like that do the installation. I would check into it or have someone you can trust look at it. Good welds don't need to be ground on.