Trax is 18" tall and jumped 20" in competition until he was almost 5 years old with no problem. We practiced at 22" for the 20" class and he always did just fine. If anything, it made him think about the placement of his feet a lot better. Now that he got his challenge measurement, he jumps 16". I practice him at 18" or 20" now. In USDAA if he was in the Championship division, he'd have to jump 22". I'm confident that he could do it and would without any complaints but I'd rather not do that for the long term, so I jump him in Performance, BUT to help my daughter get her Starters Relay Q, I may enter him in Championship just for that one Q and team up with her since her dog is only 14.75" and jumps 16 
