I voted 6906 because it's the only compact 3rd gen I own.
Compared to my 5906, 5946, and 4566, it's as light as a feather.
I'd rather carry the 8 shot .45 than the 12 shot 9, but the 6906 is so much lighter.
I think a 3913 would be better but I don't own one. So........
That said, I carry my SR9 (full size) more often than I do the 6906.
17+1. Thin. Light. More grip length for better control.
Longer barrel for more velocity.
100% reliable and a cheaper/easier to replace.
If I go sliding down the pavement, I'd rather it be my Ruger getting road rash, than my Smith.
Back to only 3rd gen choices. Mine is a 6906.
I'd love to have a DAO 30 or 59 series compact for carry, but haven't found any for sale at a price that would not put me on the losing side of a divorce case.