3N defense is one of the strongest. I dropped 4 defenders long ago in favor of midfield control. The best defense is not letting the opponent to have chance created in the first place.
3W defense however is rather aggressive instead of trying to defend, that can result in high score count...

Opposing AML+AMR can be countered by regular ML+MR, DML+DMR or two DMCs. Pair DMC being one of the strongest counter against front hexagon (X-X-2n-2w-2)

AML+AMR have a slight advantage if the only flank are defenders, I can't say 4 defenders is particularly good in this case.
Front hexagon counters vanilla 4-4-2 slightly, noticable but not significant.

4-defender is a valid counter against formation with 3 STs though.