I like punch bait when the current is low, or in some slack water under a slip cork. The cheapest, lightest slip corks you can get. Don't get some fancy Thill slip bobber...get these
. 3 for $.89. The key to a slip bobber rig is to go as light as possible. Channel cats can be very sensitive to resistance, and if they feel any, they will spit the hook out. Put just enough split shot above the hook to make the float stand up. #4 or #6 trebble hook. Watch the bobber closely...as soon as you see it go under, set the hook!
CJ's punch bait and Danny King's punch bait catch channels. Go over to the catfish section of TFF and find Stubby. He sells a cheese bait that flat out catches fish. The only thing I've had a problem with stubby's bait is that it doesn't seem to stay on the hook as well as punch bait, but it's normally not a problem.