50 meters (5 atmospheres) should be ok for minor water activities, but many people feel showers are a different story altogether. You have water coming out of the shower head under moderate force, hot water instead of water at body-temperature...and now you're asking for trouble. You're gonna accidentally do something stupid like climb into the shower with the watch's crown in the OUT position and next thing you know....your shower is allowing the watch's movement to take a leisurely soak. Not good at all!
You could do what men in the 20th century did and just take your watch off before you get near water, or, do a brand new search of field watches THAT HAVE SCREW-DOWN CROWNS. These usually will have a higher water resistance rating. Another choice is to look for Diver's watches that look less like dive watches and more like field watches.
In other words do a reverse look-up: make water resistance of at LEAST 10-20 atm (100-200 feet) your search priority. And from those candidates,then look to see which one(s) appeal to you.
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FYI
I just looked at Hamilton's website, and they currently offer the Khaki Navy Scuba Auto. Water resistant to 100M (330 FEET), screw-down crown, ETA automatic movement.