About a month ago I shot a 5x5 bull at 30 yards using a 168 grain TTSX out of a .30-06 at about 2900 fps. It was a high shoulder shot and the bull dropped at the shot and slid back down the steep hill about 10 yards. I found the bullet under the hide on the far side with all the petals gone. The bullet passed though quite a bit of bone so that's probably why the petals were lost.
The TTSX worked great at close range. If I expected to shoot at 400-500 yards I would probably choose another bullet that expands a bit more easily.
I've been using 150g Partitions out of my 270 Win at close or just over 3000 fps for longer than I care to admit for just that reason. They expand reliably out to 600 yards, and up close (15 yards) they are devastating with the back half always penetrating deeply. For larger calibers (375 Weatherby, 500 Jeffery) I prefer A-Frames or TSX's because the shots tend to be closer and the game is sometimes dangerous.
