It is down to the prep and quality of the process. A while back a local company powder coated their products, many being for underwater use in the sea. I had a visit there and was impressed.
I would be happy for it in many applications where there is no heat, significant flexing, abrasion. Long term if the coating cracks then it creates a deadly rust environment under peeling areas.
Wire wheels? If done properly then it should be ok but keep an eye on damage from stones/kerbing etc..
