A quick snoop around various watch forums indicate that the brass one is a good watch. I'd go for it if I were you. Helson don't sell shite.
Just remember to turn the bezel at least once a week...or not if you don't mind it seizing after a while. There is a reason that most dive watches are steel!
Ah, cheers. Bronze! I knew I missing a key detail.
Well, in a way the patina is a secondary thing. Mainly after reliable dive watch that's a bit different to all the stainless offerings.