"Best" 12BH7/A tubes?

What is the sound character of the various 12BH7 and 12BH7 tubes? Different manufacturers, different dates, different construction types... How would you rank them in "quality"?
I just put a pair of NOS Brimar's in my power amp. They replaced a pair of black plate RCA's. I was really surprised at how much better they sounded across the board.
Thanks, Thorman. Pinch plates? What type of getter and lettering? Ditto RCA. You think the Sylvania has the best balance of detail and body?
Pmboyd : I can say that the 12bh7a Sylvania works best for me..Its a matter of system synergy..The 12bh7a Sylvanias I use were purchased at Tube World and they usually have a few versions..I use the Yellow Print...listed as .."Pinch Plates".. They vary from $70 per pair to about $100 pair depending on which yellow print you buy.....These are neutral sounding and if you need warmth you will have to go to another tube...Possibly RCA Grey Plates..Wish I could give you a more difinitive answer but its a crapshoot..The only way to know for sure is try one and go from there......Good Luck........
12AU7 is pin-compatible with 12BH7 but not equivalent. For example, if the 12BH7 is used as a driver tube, a 12AU7 will not do.
Best wishes