I've used Rust-Oleum Hard Hat on quite a few "big boy's toys" (lawnmowers tractor M/bikes gates etc.) over the years. Very easy to use, reasonable coverage but need to apply in light coverage or the paint seems quite prone to "run"
Great product but costs seem to be getting higher all the time. I may go back to contemplating whether ease of use outweighs costs compared with a product such as Hammerite