Questions for BAT VK-75SE owners

According to Victor at BAT, it is not recommended to roll the six second stage 6SN7s with NOS because they may fail due to the high (450V) plate voltage. Does that mean the VK-75SE is over driving the 6SN7? Will that shorten the life span of the tube?
Well, I didn't know that. And I have RCA 5692's in that spot. I've had one fail over a year and a half...not bad average...about the same as the sovteks I had in my vk60's...

That's for the info though.
4 fun, I put my Sovtek 6sn7's back in this morning. Took the RCA's out. Sovtek's have more dynamics, more highlighting, more bite. It's subtle. Highes a little sweeter, more relaxed with the RCA's. I'll likely put em back in...not as much of a diff as I thought. it's just one of 3 gain stages in that amp...
Thanks for the update. I think you just answered a question I was about to ask. I need to replace the old tubes, I think I will just get the Sovtek or maybe the Electro-Harmonix which seems to be better built. Any experience with those?
Hi, I haven't tried the EH in the 6sn7 spots...sorry