I have never recovered a bullet from a deer. All of my shots on deer have been 125 yards and under and where very much a pass though. I have seen the differences in bullets though in shooting water jugs and recovering the bullets in the spring time after the snow has melted. Core Lokt's dont hold together quite as well as the Hornady Interlock bullets do, but none of the deer that I have ever shot have been able to tell the difference. Its all about shot placement on deer. Now your larger deer, like the high mountain muleys and the large white tail, some will say that you need a high end bullet and for my money I would probably want to use one too. But for your run of the mill residential deer that I get a close shot on, I just use the old tried and true cup and core bullet. My guns seem to like them well enough and they dont break the bank.