Is Fractional Laser More Effective Than Dermaroller?

I already finished my 6 sessions of my dermaroller, and for me i can only seen at least 20 percent improvement in my scars. Now I'm planning to spent my money for another session but then, a dermatologist suggests that fractional laser co2 would be the best option for treating acne scars, however she admits that dermaroller and fracional laser has the same effectiveness, and the prices are different, fractional co2 is much more expensive. I need some advise from you, do you think fractional laser is a bit effective than dermaroller because if so I'll chose fractional co2 and if u say they have the same effectiveness then I'll chose the dermaroller which is more cheaper. thanks!