The question is what you mean by "distinct improvement." If you set the bar too high, your expectations of these treatments will never be met. Also, no one can predict exactly what result you will get and this further complicates the process. And unfortunately, some will tell you whatever you want to hear to get your business.
My advice would be to go to a Board Certified Plastic Surgeon or Dermatologist and ask them directly what you can reasonably expect. Look at photos of their own patients, not those given to them by the laser company. Listen to your gut instinct and hold off if you don't feel comfortable proceeding. Just don't set your expectations too high or you will be disappointed for sure.