That's my site. I'm not selling anything --- just helping. What I present are application" guides with easy-to-understand-and-apply principles. Nothing anecdotal.
In order to effectively utilize a PA system, you need to have a firm grasp on the principles at work. Trying to use a PA system without applying proven, factual principles would be the same as trying to perform a magic trick without no real understanding of magic principles. Doesn't matter if the trick is "Hot Rod" or "Bullet Catch", and it doesn't matter if the PA system (or wireless mic system) is tiny or truck-sized.
I don't offer buying advice. What I offer are easily-digestible facts that will help you make your own decisions. Let me know if you have questions about audio principles or their application.