I can get 5 (or more) now as I only use my DEs for cleanup after I use my straight for the majority of passes. When I was shaving exclusively with a DE I would change blades after 3-4 shaves. Blades or cheap so why be a piker?
Three or four, then out the door. The blades are the most affordable component in our shave kits, and at the same time can really affect the outcome of the shave.