Hmm, well the best price I could find on Buffets is from an online house that carries them all, namely thomann. It's pretty easy to see them all, and their UK pricing is better than Yamaha's USA pricing (dramatically better in some cases), and unlike Yamaha it is not prevented from buying in the UK, just be sure you get a 440 model if buying for stateside use.
I've spent a lot more time analyzing the Yamahas. So I understand their lineup better:
They have three professional lines in order from bright to dark tone (this is oversimplified I know):
Standard model and (USA) price Oct/2023 - Yamaha will not let foreign sellers ship to USA, otherwise you could get them for much less out of the UK or Korea. Not sure why we pay more here.
CSVR $3700 - 17 keys, silver
SEVR $3700 - 17 keys silver
CSGIII $3800 - 18 keys silver (low pitch correction key).
Up-sell artist models:
CSVR-ASP - $6500 - 18-19 keys, silver (left Eb standard, low pitch correction key optional)
SEAM - $6500 - 18 keys, silver/gold (left Eb standard)
CSGIII/HL - $5200 - 17 keys, gold (Hamilton plate - left Eb key and low pitch keys are optional, price is without either, the upsell part is the gold plating which has a better sound according to it's fans).
Both the CSVR-ASP and the CSGIII/H models offer "improved" tone over the base models, not sure if the SEAM actually sounds different than the SEVR.
Some of the up-sell Yammies are more popular in A, as they are considered the best A's that can be bought right now by many but there is not as much consensus on the Bb's.
Some of the upsell models are hard to get, don't know why.
It is also worth noting that the CSVR ASP has a slightly different bore than the CSVR.
We could also talk about the 450 and 650, similar to E12 and E13 I guess, but I didn't research them as much.
I can find principals in symphonies around the world that use them all (not the 450 and 650) - (mostly the upsell models AFAIK), but none of them are dominant from what I can tell, as all seem to be useful to somebody.
I don't think cost/benefit applies much here, it's what you want and are able/willing to pay for. One person's 'benefit' is another's 'yuck' from what I can tell.
Buffet is playing the same game, the R13 hasn't been their flagship model for a while now. And their other models similarly cost way more, especially in the USA where the price seems to almost double in some cases. Tosca(nini) anyone?