Low medium, or high? - Vortex Tactical 30mm Rifle Scope Ring - 1x Per Package

I wish the manufacturer would AT LEAST make a suggestion/recommendation as to which scope ring would match with their scope. For example (and my experience) the "LOW" mount rings are TOO low for the Vortex Crossfire is you want to mount on a flat top AR. You will need a "HIGH" because of the size of the objective and/or eyepiece. Of course a lot of this is dependent on the stock you are using AND your skeletal structure and distance from cheekbone to eye. ok... i think i understand why the vendor doesn't make a recommendation :-)
I can't imagine a scope that would work being mounted on "LOW" mount with a 30mm tube. When I removed the stock and rested my cheekbone on the bare buffer tube...THEN it worked, but with a stock on it??? forget it.
Hope this helps somebody and keeps them from buying the "LOW" mount.
Like most, I now own one of each.
What I WOULD REALLY like to see is a description on each scope ring giving dimensions from the top of the picatinny rail to the center of the scope ring so I can make an educated purchase.