If fairness, everyone has their own comfort measure for what they want or need for ER. Today, with all the lightweight rifles out there, more ER is probably needed unless you're getting then in mild recoiling rifles. I happen to like rifles that typically weigh around 7.5 pounds or slightly more in my rifles chambered for 280 Ackley and 30/06, so I really don't need 4 inches of ER. Last year I got banged by my 50 cal ML that was wearing a Leupold 1.75-6 scope and it hurt like hell. That scope was one of Leupold older "shorty" models that didn't have the rubber ring around the eye piece either. IIRC, Leupold stated that scope to have 3 3/4 th's inches of ER at 6X. I was shooting the rifle in warmer weather and w/o a hunting jacket which is why I probably never noticed the ER needed prior to that. That same day, I also got brushed by my 300 WM which is a 9 lb rifle all up. That day was one of the reasons I bought that Leica ER scope that has a solid 4" of ER across the power range. Problem solved, regardless of what I wear clothing wise to the range from that day on.
