For Roughout or Smoothout, see Tucker blog...
Tucker Gunleather Blog » Blog Archive » Rough Or Smooth Side Out?
Tucker Gunleather Blog » Blog Archive » Rough or Smooth Out - from a Customer’s Point of View
I regards to front sight style, I imagine that if one has a exceptionally large front sight (i.e. XS Big Dot) they may require the Extra Tall option.
But, I am just guessing and could be way off. I would give them a call tomorrow to inquire.