Your region of the country may be different, but in my recent trip to the James River in Virginia, we used fresh cut shad that worked very well for us. The frozen shad didn't seem to be as effective. Remember though, big bait will catch big fish, because with blue cats the smaller ones don't seem to mess with larger bait. My role of thumb was to use a piece about the size of my fist, but no smaller. If you're fishing for numbers, you could downsize your bait, because I'm sure the big ones still wouldn't pass it up.