It is pretty easy to accommodate a little too much drop, not so much too little drop. Most Italian O/Us have too little for me. Beretta is the exception. DAC is more important than DAH, but in most cases too little DAH means too little DAC. Too little drop and I have to float the bird, and that is a recipe for poor shooting.
I handled three of CSMC's Revelations yesterday. All had perfect drop for me. I think Lou said they were 2 3/8" at the heel, but the catalog says 2 1/2". Anyway, it was a fit for me.
SRH
I measured my new Revelation it had 1 1/2" drop at comb and 2 1/2" drop at heel. Perfect for me and with the thin comb, I need no cast.
