The easiest way to check is by logging in and verifying whether you can see the discounted prices.
For example, consider the JuJuBe brand page: http://www.pupsikstudio.com/shop-by-brands/ju-ju-be
This is what a non-VIP customer (and all non-logged in customers) will see. All prices are shown as full and no discounts are visible.
And this is the same page as seen by logged-in VIP customers. The full prices are crossed out, discounted prices are shown in red, and there is a message "MEMBER'S PRICE" next to the discounted price.