Does anyone know these tubes?

I had ordered a pair of NOS Sylvania 6CG7 via the internet. Instead I have been sent 2 GE JAN-6CG7, marked 82.52 33173 on the tubes. I would guess 82 is the vintage (the boxes are marked A.9/82) and since they are JAN versions I trust they'll be fine in terms of build quality. Does anyone know whether these early 80s GEs are good for audio purposes, though? Or should I insist on Sylvania (of which I don't know the vintage)?
Thanks for sharing your expertise.
Its very possible they are the same and branded for Sylvania.I am not an expert but I would say that its a possiblity they are the same tube..
Perhaps I've been throwing in too much detail, it would be an extreme coincidence if anyone had tested exactly these tubes.

I guess the core of the question is whether vacuum tubes General Electric built for the army in the early 80s are any good?
I have been using the ( 1986 )Jan GE 6201 ( 12at7 )for years and though its an inexpensive tube,it sounds good,totally reliable and very easy to find in the marketplace..Some may scoff at it becuase of its low cost but for me its one tube I never worry about..