Knowing the reputation of Meguiar's and their long history, knowing their products, etc., I'm confident this brush went through rigerous testing before it met their approval. They know as well as we do, they can't tout and promote their products and how good they make your car look, how well they protect it, if they're seeling you a brush that will mess it up before you get those products on the car!
I've not used it, but I'd trust them with it. I may just have to check it out myself. My concern would be how well it can clean. But that too I am sure they've tested well. So I'm sure it must do a great job of that as well.