Dear All,

Help in taking decision , confused if I should go with canon 400mm f/2.8 + 2Xconv OR Canon 500mm f/4 +1.4Xconv.
My main subject of photography is mammals and very seldom birds.
Kindly comment on following.........

-AF speed of both lens with converter on Canon 7D body.
-Sharpness.
-Results of both with and without converter.