Those specs don't add up. At 12V, 6A would give you 72W. It says 6A/meter, but 72W/5meters.
More likely it's 6A/5 meters.
Anyway, either of those connectors should work. They are not the same, note the first is 120mm long, the second 158. Believe it or not, that is quite possibly enough to explain the factor of 3 in the current rating. Current ratings are a bit dodgy. I've seen connectors with three different ratings from three different agencies.