RE: Burris sig series
I had one for a few years it was good but for the money they fetch in my parts I'd take a Zeiss Conquest or Leupoldover the sign series. To my eye both are optically better. One thing I will saythe sig. serieswas very good at tracking POI adjustments,just like my conquests have been. I have heard some terrible references to Burris CS on websites while both other get good ones, though never used any of them personally so can't comment on validity of the claims. I personally see no need for the ballistic or 12x range on a biggame rifle but each their own.
Good luck