Truth is that if I could afford to shoot several driven shoots a year the cost of the better Bismuth ammo becomes unimportant. You pay several hundred pounds and you are not going to cry about 30-40 more pounds for a box of ammo when you might use two or three on a great day. Steel might be cheaper but premium steel is not that much cheaper and the cheap stuff is almost like what we use to use 30 years ago. Very range limited for many.