For a long range varmint gun should I spring for the MK4 leupold 6.5-20x50 or 8.5-25x50 IR or stick with a Vari X111 8.5-25x50 with Varmint Hunter Reticle. These are the models I have chosen and I am now wondering would I be better paying the extra for the MK4 series seeing as the .300 RUM is a hard kicker. I have the VX11 mentioned on my .243 but I am wondering if the .300 RUM warrants the MK 4 ?? I also love the Varmint Hunter reticle, but realise glass etched is much better. Thanks Folks.