What would you get? Skimz SM 121, SWC160, Nac6A, Nac7 or NAC9?

[RuGlu6]

If you had a 66 gal tank (SPS dominated with three mid size (3") fish) what would you get, if you had to choose between these skimmers and why? Also i am trying to find out the size of the neck of the cone Nac7 skimmer, does anyone know ?

It is stated that Nac7 Cone skimmer is 9" at the bottom but what are they at the neck in inches? Almost looks like the chamber of the Nac7 is similar diameter at the top as Nac 6A and if so the these two should have very similar performance in terms of contact time and air to water mix ratio especially due to the fact that these two have the same water pump atman ph2500.

And yet Nac7 is rated for more gallons.

I'd like to overskim so this is decided, but still wonder what others think.
thank you.

Nac6A
.
NAC7
.
SWC160

Or
SKIMZ SM 121