2019 300B tubes that are worth the money?

thanks for all the input, folks.  though in truth I'm feeling as confused as ever.  These things are so expensive, I'm just afraid of shelling out 500-1500 dollars and not being able to tell the difference.  maybe I'm happy and should just leave well enough alone.  :-)  wish there was some way to audition tubes in my amps...  need a local LA audiophile club...

So I ended up buying a used pair of KR 300B's.  The price was right ($500) and I'm very happy with the sound.  Hopefully they will last, but so far, so good.  I was a little surprised at first as overall I would describe them as more laid back, quieter, and mellower than the TJ's I had, but there is also more and tighter low end.  SET amps plus Klipsch speakers can be overly bright and the Czech glass brought balance to my system.  (also, my great grandfather was a Czech glass blower, and though I never new him, I think that heritage weighed on my decision!) 

well as the OP I thought I'd chime in with an update on my 300b status as this thread has somehow stayed alive and relevant.  As I stated previously, I ended up with a (supposedly) lightly used pair of KR tubes that I bought for $500 and was very happy with the sound.  But.... a few months ago one of the tubes slowly began to fail  (started randomly getting very soft and cutting out).  It was very hard and disappointing for me to admit the tube was going bad.  And then it was completely gone.  So I went back to my TJ/full music cheapos and was in anguish shopping and researching and rereading all the 300B reviews and trying to prepare myself for spending close to $1000 on a new pair of something.  Make a long story short, I settled on the PSVane Western Electric replicas and ordered through a somewhat dubious looking Chinese website where I paid only $600 (hifipartstore.com, if you are interested).  That seemed like a pretty good deal and the reviews I read seemed mostly very positive.  Took two weeks to arrive and I put them in yesterday... and.... I AM BLOWN AWAY!  My system sounds better than ever, the soundstage is enormous, the tone is warm and deep and detailed, the separation is fantastic.  Last night I couldn't stop listening to vinyl and heard stuff in old Fleetwood Mac that I'd never heard before!  I liked the KR tubes quite well, but without doing an A/B comparison I feel the PSVane WE 300B is superior.  Hopefully they will last awhile, but for now I am a very happy customer.  Cheers and good luck to you all in your search for audio nirvana.