From my experiences it is clear that single gas lasers outlive mixed
gas lasers by an incredible amount.
 Colleagues here are still using an argon laser from the beginning of
the decade, on a system that is heavily used daily.  On my system I
am on my second argon/krypton laser, the system having been installed
here in mid 1994.
 The engineers pointed out that a mixed gas laser would probably not
last more than 2 or 3 years sat on a shelf ....
 Anyway, I'd suggest setting aside stlg6000 or so for a refurb on your
new laser within 2 years.

Andy

Andy Hubbard.
Confocal Microscopy Technician,
CMHT., Hodgkin Building, Leicester University.
Tel: 0116 2525625,  email: [log in to unmask]