I have just purchased a Dr Roller dermaroller 1.5mm and plan to use it once a month to treat some pinhole scarring from a laser treatment i had 3 years ago. I have just had a course of 3 dermarolling treatments by a doctor with a 2mm roller but cant afford to keep going to them when its 1,500 australian dollars for 3 and im going to need more as i still have the scarring there although there is some improvement. From my research i will need at least 6.