Yes, I'm aware of the cost difference; I own a DIY powder coating machine which has proved very useful and quite cheap to use. My present fun car (the Liege in my avatar) has a powder coated chassis. Powder coating is great but I've seen what happens when the edges get knocked off a powder coated chassis and rust starts to get underneath. I have to keep a pot of satin black gloss for touching in the damage.
I've also owned a car with a hot dip galvanized chassis (I stripped it for parts to build the Liege). Galvanisation on a car chassis is more durable and it would be my personal preference if there was a choice. I'd pay the extra.
they put this in a tech talk long ago. They say dip so isn't that galvanized?
"Division 3: Paint Division — Priming consists of the dip process of the body frame for anti-corrosion and the color side for painting the body panels utilizing an environmentally friendly “dry process.”"