I have few questions about your products. Which are the main diffrence between the one with 9 lasers and the one with 7 lasers? I know that the one with 7 takes more time , but my question is : is there any other diffrence in the effectiveness or other?

I notice that LaserComb Advanced 7 is not written that is approved by FDA. (see this link )
Is this metter?

Thank you!