I've had a laser printer for just over2 years now, and the 'replace toner' light came on about 4 months ago.

Since then I've printed on average one page per day (home use), and it is still giving good results .... so why the early warning light??

I'm sure the manufacturer (HP) will say it's to give customers ample time to ensure replacement toner on hand, but does seem a little premature.