I just had a great conversation with Oliver at Tab-Funkenwerk. I had sent him a V78 to inspect and service that had I found on Ebay for way less than the usual price. He told me that the unit was in "like new" condition and that all he recommended was to replace the power supply capacitors. Other than that, the unit was ready to rock and that it was one of the nicer units that he has come across. So, the unit is on its way home to me, still with the tubes that were in it when I bought it - they tested fine. Can anyone tell from their experience how long the two EF804S tubes can be expected to last in a V78? These suckers are expensive, around $100/pair for NOS Telefunkens, so I was wondering whether I was going to need a pair per year or a pair per decade? I realize that tube life varies, but I'm just looking for a ballpark figure. Given the way tube prices keep heading straight up, I just want to know whether to go shopping for a spare pair, or whether I should be looking for a dozen?