Best 845 tube out there?


I am running a pair of Cary CAD-211AE monoblocks with the standard no-name Chinese tubes shipped by Cary. Whilst I am happy with the sound, I think I should buy a pair of 845's to keep as backup in case something happens to these tubes.

Because I will need to buy FOUR of them, this rules out any tube that sells for stupid money (e.g. vintage RCA 845 tubes).

The only current production 845's I am aware of are:

- Shuguang 845 "standard"
- Shuguang 845B
- Shuguang 845C
- Shuguang PSVANE 845
- KR Audio 845

I have found reviews of the Shuguang 845B and 845C, but there is virtually no information out there on the new Shuguang "psvane" 845. Has anybody heard this valve, and is it a noticable improvement over the 845B and C? Also, what do people think of the KR?
amfibius
@t_ramey 

Great question.  My honest answer? ...this thread, mostly.  I reread the whole thread again (I've probably read it through 3 times now over the last 6 months), and some folks whose opinions I trust from other topics seemed to get enjoyment out of the Psvane WEs...and most relative to the Shuguang Bs (and As). 

One poster noted that the Elrogs blew the Psvane WEs away (and I trust his feedback from reading his posts over the years), but since I own the Elrogs, and they didn't blow the Shuguang As and Bs away in my Melody on my my two sets of speakers, I felt it was a decent dice roll to try some WEs for the Melody, since again most posters felt they were an upgrade to the Shuguang A & Bs.  I've never owned any Psvanes of any type for any of my amps, but marketing aside, I still feel like I've read good reviews/posts in general on the brand, and this is their offering that is most interesting to me, despite it's $800 cost for the experiment.

As to why not Shuguang WEs?  Only in that I didn't yet find a side-by-side, other than a suggestion that the Shuguang is newer and based on a better retro design--I can't confirm that.  They are cheaper--which is also interesting to me, but doesn't necessarily mean anything in the rest of this context.

Knowing me, this exercise and discussion may entice me to later also order a set of Shuguang WEs too.  You know--for "science."  My wife asks me when all my "science experiments" will have a financial payoff.  She doesn't like my response is that "the financial payoff went to the product manufacturers."
@t_ramey  Thanks to you too...please continue to keep in touch as it seems posting Melody 845 owners are few and far between.

@charles1dad    A personal note of thanks for your general knowledge and approach to this "sport"...I find your posts in almost every thread that interests me on this site...I think I've followed in your footsteps on numerous purchases and your findings are always spot on.  You've heard and provided great feedback on almost every tube product I own or considered (and many I own largely because of contributions you've made to the decisions).  No pressure!

Great thread--thanks to all for keeping it going.
I own 2 pair of matched Psvane WE 845s that replaced Sophia's best 845s and the improvement was immediate throughout the frequency spectrum.The Sophia replaced Shuguang.Rachael,at Grant Fidelity is wonderful to work with too.