I'm by no means an expert on whoa training, my impression on either a table or barrel is to put the dog in an uncomfortable position or place so they are focused on you and the command. I have used my hunting buddies barrel and I have used large diameter oak logs chunks. My Britt pup loves to be out with me when I'm cutting firewood so for the very large pieces I cut long and place her on the chunk and work on whoa, then I throw balls or sticks to reinforce the whoa. I think the barrel is more in-nerving for the dog as it is slicker, less space and more unstable. I don't think you can go wrong with either one, this is just my 2 cents. I'm sure more experienced trainers will chime in.