I usually get 4-5 shaves with the Derby, my primary choice of blade.
Wow, I was amazed reading this thread, I go a full 7 shaves (1 per day) so 1 week before changing and I'm fine on my last day. I've always been lucky that I didn't have a heavy beard but I'm amazed that most folks have to change in 5 or less days.
I get two shaves per blade. Sometimes three. But I always toss all blades after two shaves (except Astras), so . . . two shaves.So the Derbys are a great blade and give much closer shaves than the Murkers but I am only getting two shaves per Derby blade.....is this normal??
I have been giving Derbys a go as well. I have a Red Tip SS. Do you use one side one day and the other side the next or do you switch the blade around according to the number on the edge. For eaxmple (1) on Monday (2) on Tuesday (3) Wednesday (4) Thursday?