I use the Aimpoint Hunter S34.
The difference between the 'long' and 'short' Aimpoint Hunter is purely cosmetic.
Obviously the '30' has a smaller objective than the '34' (mm)
I can't compare it to the '9000' series but my understanding is that the technology used in the various Aimpoint red dot sights is basically the same.
Great for use on a Scout rifle (light, short, pointable, ching-sling) and for driven game.
Great for use in dense cover where shots are typically close-in (30-60 yards)
Much quicker to deploy than a more traditional rifle scope, both eyes open instinctive shooting, no parallax issues.
Holds its zero very well
Not so great for twilight conditions, or for long-distance shots (over 100 Yards)