Fall is here and I am looking start leaving my dogs a little longer. I am thinking of getting a # 3 blade, it leaves the hair 1/2 inch long. I have Oster plastic snap on combs, but I am thinking a blade may be a better choice. I also see a lot of groomers talk about metal combs, I guessing they are thinner, and go thru the hair easier. My question is should I invest in a couple of 3s or go with a metal comb set ? Thanks in advance.