I have found some used DMTs for pretty cheap and I was wondering how well they wore. Would it be worth $15 each for them? I have a choice of 120, 220, 325 and, 1200. the 1200 is in a smaller 6inch size and I have emailed the seller about the sizes of the other ones. Since a new DMT D8C is $54 I'm hoping these are usable for me. I can get multiples for cheap. 120 seems too rough but the other 3 grits interest me.