LinLai WE 300B or the LinLai Global Elite Permaloy 300B tubes ?

+1 on Telefunken ECC83. Sounds better than Gold Lion in my amp - more detail. For power tubes, I was using Valve Art 300B's and then found Shuguang Black Treasure at parts connexion for half price. They both sound good, with the BT sounding more refined and better bass. At DIY audio, where I purchased my Elekit TU8600, they speak highly of the LinLai Cossor WE300B. BTW I love the TU8600 - best sounding amp I've ever owned.

@sns ,  Thanks for the details on your experience in upgrading the CSL preamp to MK II.  I've been considering this upgrade since it was first announced, and contacted Israel who didn't give much detail on what sort of improvements one might expect.  Did you buy the Amtrans and send it to Israel, or did he order it for you and do the installation.  I love my CSL and consider it my destination preamp, so I'd happily part with it for a while to upgrade it.

Certainly, Mki version doesn't have problem with timbre, its just that with Nichicon Muse vs. Rubycon just a bit more, when you hear you'll know. The greatest upgrade is the more precise sound staging, imaging. Can't recall if he or I brought up the Amtrans, I had seen them at Partsonnexion, and having seen the stock cheap Chinese volume selector in mine up close and personal I did speak to this directly. He responded the Amtrans would be big upgrade, I didn't even care to ask him about nature of upgrade, or any of MkII upgrades in order to mitigate expectation bias. Anyway I ended up purchasing Amtrans through Israel. I will say the upgraded volume transformers are what you're spending your money on here, I imagine Amtrans add precison to some degree. The cheapo Chinese selectors are real junk plastic and metal, Amtrans precision parts! Once you touch and see them you don't want anything less.
I believe the only place you can get Cossor versions of LinLai is ebay, they aren't intended for US market, not sold at LinLai factory official US website. Which means they are lesser quality if what LinLai themselves claim, which is they only send their best tubes to North America, all marked only as LinLai, no Cossor.

@sns,
I was aware of the MK II upgrade when introduced a couple of years ago. I had no interest at the time due to my complete satisfaction with my MK I original model. I could see where an improvement of the volume control transformers could make a difference. The capacitors you refer to, are these in the power supply chassis?

Interesting comment about the stock vs Amtrans volume control knobs. I used to chat with Israel occasionally but it has been quite awhile ago. I may have to get in touch again. I plan to keep the Statement  line stage forever (LOL)  so may strongly consider the MK II upgrade. Thanks again for the insight/feedback.
Charles

Two caps in PS, two in signal chassis. As for improved timbre, I'd suggest some or most of that improvement comes from both volume transformers and Amtrans volume selector, although having used Muse caps in prior mods in other equipment I can assure they are a very natural sounding electrolytic cap. Both VS and VT in signal path, have bearing on timbre or coloration of the entire pre. I'd also suggest the Amtrans is superior here to cheap Chinese upgrade (stock Chinese volume selector even cheaper than upgrade) unit here, much better metallurgy and no dialectic. Amtrans precise volume tracking is likely responsible for much of the improved sound staging and imaging I'm hearing, doubt the Chinese unit can replicate this. I did mention this particular aspect of improved performance to Israel, he concurred, much of this improvement due to Amtrans.