I had privium for 2 years, but I was also working part-time in the NL. I have sky priority. In my experience:

• The lounges were the nicest part.
• Passport control: 50% of times the privium gate was not operative OR (this happened at least 3 times) I was sent to a secondary screening to check my purse or handbag and swipe my belt etc after crossing from S->NS through the privium gate, so I would have been better off with regular EU passport machines.
• security: pretty much same as with sky priority. Be careful with getting sent to the line used by crews and passengers on wheelchairs or with babies.

If i had a car, I would have had the greatest advantage of the parking, but coming on train the difference was not that noticeable, mainly the lounge.