New KT150 tubes?

I am at the 1,990 mark on my Ref 150 KT120s and was curious about replacing with KT150s. I called Kal at ARC who has been an invaluable resource in the past. I asked when ARC would be done testing the KT 150s. He told me that ARCs position is that it views the life testing of Kt 150s as a "rumor". He could neither confirm nor deny whether that tube was being tested or if was even being considered for testing in the current line. Of course, he was very polite but very firm. I ordered 8 KT120s

I too waited anxiously for ARC to bless the KT150 s with the Ref 150 when I reached 2,000 hours on my KT120s in the summer. But they didn't, so I purchased another set of ARC KT120s.
I have owned 2 ARC amps and 3 preamps and have always purchased my tubes directly form ARC due to the comfort factor, but the reports were so good on the KT150, that I managed to meet with an insider at ARC who assured me that, unofficially, the KT150s were recommended for the Ref 150. Purchased a matched set from Upscale and can say they are better than the KT120s. Just sorry I didn't take that shot earlier cause I now have a full matched set of KT120s with only 500 hours on them.
Go with the KT150s. You won't regret it.