Never be fearful of quitting a show that you've always participated in. If the show doesn't have the impact and the results you need, just quit. However, have a plan to divvy up the funds that you would have spent and allocate them to other marketing campaigns - advertising, direct mail, public relations or updating your trade show booth. Make sure to let your customers and prospects know your decision and why, so that you prevent any false impressions that you're having financial difficulties. Let them know that you would rather give them added value than spend the money at the show. You want to make sure that your not being at the show is a benefit to your customers.