I’ve never dealt with motorboat fuel so I can’t really compare, but I can say that it’s not “horrible” in a certain sense - the stuff isn’t sticky and evaporates pretty quickly, it’s easy to wash off, it’s not sticky like jet fuel (it’s almost water-like), it doesn’t smell bad and it’s not as combustible as jet fuel.

In the health sense - well, have you ever bought canned 1970s LA air and breathed it in all day long? That’s what you’re doing to your lungs. And if you handle it up close, most folks don’t wear gloves and it readily absorbs into the skin. It’s basically what happened to the boomers in the 60s but today.