I have sighted my off-set iron in at both 25 & 50 Yards. I prefer mine to be zeroed at 50Yds.
Here is data from my rifle...
Zero at 25 yards it shoots -2"@10yds, 0"@25yds, +2.5"@50yds, and +3.75"@75yds
Zero at 50 yards it shoots -2"@10yds, -1.5"@25yds, 0"@50yds, and +1.0"@75yds
As for rotating the rifle, I just rotate my elbow out. Never losing my cheek weld or seating. I find this is the fastest transition.