I used to use a lot of 139 gr Interlock Flat-bases, which killed deer faster than lightning. About 9 out of ten exited. Then I moved to the 154 for the longest time, just for a little added insurance on moose and elk. Whether it helped or not I cannot say, but it did take a little of the wow factor from the deer kills. At one time I loaded for several friends and their Rem Mags and one with an STW. They all got 154 grain Interlocks and identical loads. Loaded up a pile of 175s for the STW guy and hes taking those on his 3rd trip to Africa now. Never complained.
I had some spectacular failures with Speers, all on the same buck. Ballistic-Tips knocked the snot out of everything I hit with them. SSTs are viscious too.