How Often to Replace Your Dermastamp/Dermaroller with a New One

[Lostandfind]

I've been considering adding dermastamps to my regimen. I think if if I sterilize my dermastamp with medical alcohol everytime before and after using, the so-called infection risk is quite low. BTW, the topical I've been using also contains medical alcohol, which may further lower the infection risk in my scalp.

Is there anybody who's been using a dermastamp/dermaroller repeatedly on a sterilization basis? How many times do you use it before replacing it with a new one?