I use the cheap cutters such as Hakko 170's. They're sharp and convenient but essentially consumable. They're made from a relatively soft steel, and wear out, usually because you cut things that aren't copper. Some components have tinned steel leads.
If you dig through someone's old tool box, you'll find a pair of wire cutters with a half-moon nick in each blade from trying to cut something hard.
Naturally my use of wire cutters is declining, due to surface mount, but some of my boards still have larger through-hole parts, and I make custom cables for this and that during prototyping.
