How long do laser sources last?

Rough service-life expectations, per published ratings and owner reports: blue diodes ~8,000–15,000 hours of firing time; glass CO2 tubes ~1,500–4,500 hours and they age even unused; fiber sources are the marathoners at ~50,000–100,000 hours.

Translate to money, not years: a $400 replacement tube over ~3,000 firing hours adds about $0.13 per running hour to a CO2’s real cost. That line item is in every machine review here, because it changes which machine is actually cheapest.