These are Vostok watches, a Russian company I like because they’re cheaper than comparable watches in the US. Each of these have different things I like. I prefer the red star, the green face, and the numbers from the black one. The scuba dude is there as a wild card because he’s pretty popular.
Neutral colors are good. I’d go with the black.
I own a Steinhart “ocean one”. Identical specs to a Rolex submariner but way more affordable. I bought one after I graduated high school back in 2009. Still works and looks great today. Definitely worth it.