I got the 530 for the buttons because I didn't like how my Apple Watch and a Garmin watch with touch screens worked when sweaty. While I knew I wouldn't sweat on the Garmin Edge like the watches, I ride in the rain often and expected it to be frustrating to use when wet. I don't know if I was right or not but I'm happy with the 530.
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"It is the unknown around the corner that turns my wheels." -- Heinz Stücke