For all the good comments I have heard about Viva Tubes I had a poor result with them in my only purchase. I ordered a Russian NOS matched pair of preamp tubes. It took several days to ship them and when they arrived they looked very used and they tested very unmatched in the 70-80%’s. They immediately accepted my return and I received a full refund for tubes and shipping upon return delivery. Maybe buying new production tubes would be a better result. Once again I am glad I own a tube tester.
