I have used both of these bulletswith success on elk. I shot my biggest 6 X 6 with the 300 grain Shockwave in the New Mexico 2004 season. Hit in the chest at 70 yards, the bullet angled forward and broke the opposite shoulder. Bull ran about 50 yards and wobbled for about five seconds before going down. Found the bullet under the hide. It had separated its jacket and core, but appeared to have stayed together until the very end of its path. Dead is dead . . . . :>
I used the 250 Shockwave last year. Hit a big cow broadside in the ribs at about 150 yards. Bullet went clear through. She was down in under two seconds.
I have been shooting the 200 gr Shockwave that past few months and intend to try it this fall in New Mexico. This load is going 2400 fps and shoots almost MOA with 130 grains of Jim Shockey Gold, and has the trajectory to go 250 yards. Having heard on this board of folks shooting moose with this bullet, I am hopeful it will have sufficient penetration.
So, in summary, I think it depends mostly on which one your guns shoots the best. These are among the best bullets out there if you are looking for a high performance sabot load.