My dies have held up just fine. No signs of excessive wear after many thousands of crimps. I use die HT-236-2C4-DIE for smaller-than-normal sized molex terminal pins, such as the ones used in the Micro-fit family of connectors. I'm impressed with both the die set that came with my crimpers as well as the extra die set I ordered for Micro-fit connectors.
Edit: Looks like that die set is up to $12. I paid $7 for it, but that was 7 or 8 years ago.