Depending on the tester you can test for shorts, and compare transconductance to new and minimum good, but you cannot tell how long they will last in hours. If you have lots of experience w that unit and that tube, you could guestimate.
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.