Air suspension help

I'm now looking at getting the Monte on air but can't decide what system to use (and looking on the net has just confused me even more.

so those of you who have air, what systems do you use and how do you rate them?

I'm torn between Airlift 3H or Accuair Elevel but are these worth the extra money over the V2/V3 system?

any and all comment greatly received.