I have terrible eyes, especially the right eye, and the 10X served me well at 629 yards with the 6.5-06. .
I built another 6.5-06, lighter weight, I hope to hunt with in 2019, this one with a Rem700 action and Bartlein barrel.
This one has a VX-6HS 2x12x42...... not that I need any more than 10X.