Can someone tell me where and which speedbag can I buy thats being used by professionals? I bought this everlast speedbag but it just doesnt bouce like professional like you see in the movies, and its not that i cant hit, i can do it nonstop for 20 min easy but the bag just doesnt bouce fast, those that are in the movies when guy hits it it bounces like 3 or 4 times befor guy hits it again and mine is like 2 times. Do i need to buy somekind of rubber speedbag instead of leather?