The key is to decide what is a good product for you. Most people want more speed, but have limited knowledge about the different aspects of agility training. The key to choosing the right product for you is to understand what is the correct fit for you. If you have a good foundation for sprinting, you should be able to choose a product to get you more speed. If you're new to the sport or you are too old to practice sprinting, you might want to spend some time with an old-school, "go slow" coach. If you want to do some high intensity sprinting, you should buy a program like Elitefts or V2. There are also a number of programs like my own. Some people are just too old for their own conditioning program. Some people are too young. It doesn't matter how old you are if you have the right level of conditioning. If you are training too often, you won't have time to recover properly. The sooner you train, the better off you will be. If you want to improve your agility, it's the right time to train. When your body doesn't get the chance to recover properly, you are putting yourself in a position where your body starts to slow down or even stop.