I have more than one of each size, plus 28mm and 18mm cutters too. Which I use depends on what I am cutting, which one comes to light first and/or which one has a sharp blade in it (or the replacement blades are handy.) <G>
I also have 2 different styles of 45mm cutters in my travel with the travel machine box. <G>
Yeah, I like to have cutters when and where I need them. And try new ones too.
Have fun,
Pati, in Phx