To hit that number of years the unit will need service on a regular basis. This is a mechanical device and just like your car to hit that many years it will need servicing to fix it when needed.
This is why most shops will just use some sub 500 buck laser printer and replace it every few years.
To reword this I think people are confusing LIFE SPAN with "Time till it needs service."
Anyone can recommend a good laster jet printer with envelope feed, with budget around $2,000-$3,000? For our business, we usually print 3,000 envelopes every quarter and about 500 text pages a month with heavy paper (32 lbs, both letterhead and envelopes). We find the $300-$500 printers just don't work for us. We are looking for a reliable printer with lifespan like 5-6 years. Any help will be highly appreciated.