Tube Tester question

[jstout66]

Can you guys help me out on this one? I have a B&K 667 tube tester which has never given me problems in the past. When I get a tv or radio, I test all tubes and replace any weak or "shorted" ones before I proceed with anything else. Currently I am working on a Sylvania "roundie" that has no color. (the color "rainbows"). I had 2 bad 6GH8's in the sync section and 1 bad 6JU8 which is a color killer / sync tube. Anyway... Got my tube order today, and I tested the tubes. Both 6GH8's were good, BUT... both 6JU8's had a dead short in the same position on the tester. I suspect I did get 2 bad tubes, but how common is that with N.O.S. ??? Would you try the tubes in the set to see if it works? I didn't want to put in a shorted tube in case it caused further problems. Have you run into a tester where it will test the same tube tybe as "bad"? and what do you think of B&K in general?? Thanks!!!!!