@ddljohn-- The brand isn't that important although it's best to buy from a company who has been in this business for some time. At the end of the day though, whether a product works for someone or not relies on various different factors. I urge you to read customer reviews which will give you a good idea about the quality of the product and how satisfied customers are with it.
The type of brace that most people use during activity is actually more like a slip. An actual brace has hinges usually made of sturdy plastic that limit movement. If you need to limit movement to avoid injury or heal from a mild strain for example, this type of brace will work. But for support during activity, the product needs to be non-limiting in movement. So a leg slip with support at the knee is best.