Welcome for Ohio, I agree if your shooting bucks of a lifetime, I'd stick with what you're already doing. I like to rattle in the morning during the rut in PA, but these are 1.5 to 3 year old bucks and will respond sometimes, but I asume the bucks you are after are 5-6 year olds and well in their ways. Your spot stalk method seems to be the norm out west so maybe thats it. If the bucks are 400-500 yds away when you spot them they probably wouldn't hear or respond to rattleing , just a guess though. I rattle thinking about 80 yds maximum range for bucks to respond its not scientific in any way. I'd like to put just one of those class bucks on the wall, you already have two, nice going! Good luck in Kansas.