This doesn’t really make sense to me given the microneedling thread. There are people who had improvement with just needling in there. Sometimes I wonder if there isn’t just one single male pattern baldness but multiple types?
I bought a dermapen from AliExpress and the main difference i noticed was that the needles are about 50% more thick than the ones from the dermarollers. You don't want to make bullet holes on the scalp, just very fine thrusts otherwise you will create more scar tissue and I think thats what happened to me.