Yes, the laser tube is a wear item, along with the focusing lens.  With average usage, the laser tube will require replacement every 1-2 years.  To extend laser tube life we recommend NEVER setting the power level to over 90%. During testing we have found that by only using up to 90% power, average tube life nearly doubles!  Replacement tubes can be purchased for $300 and can be replaced in a matter of minutes.  We recommend replacement of the focus lens at the same time as the tube.  Replacement cost is $100, can be done in under 10 minutes and requires no re-calibration.  Even though the lens may still be in great condition, invisible micro fractures will have formed due to heat cycling over its life which can reduce cut quality.