Recently I have been looking into dermarollers. I have moderate/severe acne scars and wish to rid of them. Apparently, when using a 1.5 mm dermaroller you must allow a 4 week resting period in order to allow the collagen to repair itself. Through reviews of dermarollers I have learned that after immediate use of a dermaroller micro-swelling improves the looks of scars for a short duration of time. My question is whether you can use a 0.5mm dermaroller that can be used every other day to improve the looks of scars for a short duration while between sessions of 1.5mm dermaroller that will ensure improvement of scars in the long run? Also will the combination of use of both 1.5mm and 0.5mm dermaroller be harmful to the skin and stunt collagen regrowth rather than promote it?