Anybody ever own one of these? Are they like the Winchester 97?

Not safe to shoot, according to Marlin. Unlike a Winchester, they can fire "out of battery" with the action partly open. It's a design flaw, so they're all like that.

They can fire out of battery if you push in the slide release plunger. It's a definite hazard, but it's not something that just randomly happens by itself.

And the Marlin hammer pumps were generally mechanically somewhat different than the Winchester 97