I have taken a lot of deer with Barnes buleets since 1991, and my bull. I worked at Barnes and shot their #3 loading manual data as well as all daily function and accuracy testing. I have not shot the ELD-X. I truly don't think, like the other replies, you will make a bad choice with either bullet. Deer are not difficult to get pass through performance out of a bullet. Base your decision on what shots best from your rifle and does your shot distance match the how the bullet is designed to perform. The ELD-X is designed to expand at extreme long range, and will retain more of its weight at those ranges. The TTSX will retain better weight and likely leave a larger exit at closer ranges and typically have less bloodshot meat, in my experience. If your shots are under 500 yards on average, my vote is TTSX. ELD-X further out. As long as your impact velocity is 1800fps and up the TTSX odds a to notch performer. Good hunting!