I wouldn't trust myself that far on 2" target with any of my rifles, especially cold bore.
I like neck shot on close range - no tracking, no chance of shock damage to loin.
Here is mine neck shot: http://www.okshooters.com/showthread.php?130782-A-max-vs-SST
P.S. Iron sights is a totally different set of skills IMHO, no reason to knock on glass guys.
How is it a different set of skills when it's pretty much the fundamentals? Most shooters think upgrading glass will fix proficiency, improve group when it does nothing at all.