Great but a dice roll it seems
I recently purchased three of these for my 65 twin reverb reissue and they sound awesome however I had to pull one back out due to excessive hiss and popping. The other two seem perfect but at nearly 50 dollars per tube I want them to work! The genalex gold lion premiums sound nearly identical to me and with a lot lower noise floor. For sound I would say 5 stars but maybe 3 for reliability. This could just be a single tube issue though.