Forgive me if I misunderstand your understanding of Power CMS, but I will explain how I use Power CMS.
Power CMS is used for what I term to be a basic website where a company can tell visitors exactly what they do, but it gives the company the ability to update the information on display without having to come back to me and ask for those changes to be made. Each section that you update in Power CMS only updates one section of the website. It won't automatically add a new dynamic page to your site. You would use Power CMS in its simplest form to enable a company to update its 'about us' info or 'home page' text. Power CMS is a prebuilt admin section that is very effective for such sites.
I personally wouldn't use Power CMS for a store to add new products to a catalogue. For this, I would use data assist. I am in the throws of making my own online business, but I have started with PowerStore and I am changing it as I go. It just enables me to get up and running straight away, then make changes as customers are buying from me.