Is the direct DC power connector weak? It looks a little weak compared to a Thinkpad connector but maybe its fine.
It's not weak feeling to me at all. I came from a MacBook Pro with MagSafe which was exceptionally hard to break, so by nature it does seem weaker than that, but not bad
Will this 98Wh USB-C battery charge it?
It might, but not quickly. They Vega models ship with 150w PSUs
Is the official Spectre USB-C battery too expensive for what it is?
Yes. It looks like a 60w capable pack so a third party could match it but 60w won't charge it very quickly
How is Linux working with the latest 4.18 or 4.19rc kernels and latest Mesa stacks?
Has anyone had success with OpenSUSE Tumbleweed?
Has anyone had success with Qubes (the normal non-Vega seems to work by report)
I have no idea, don't use linux
Has anyone had good results with undervolting and what are their numbers?
I was able to run a 100mV undervolt that was fairly stable. CPU temps didn't get about 80c. Just up to the silicon lottery
What kind of battery life could I expect with Linux using mostly Visual Studio Code, Firefox and mostly light-to-medium PHP in an Ubuntu VM? Maybe with 15-20 minutes of non-GPU assisted youtube.
I have no idea, in Windows I get about 5-6 hrs of Visual Studio Community
Has anyone tried the Toast wooden skin? It seems pretty cool if I could get it for less. I'd prefer probably just a more fitting carbon skin but this does have charm. Does it interfere with thermals? Is it a stupid idea or is it cool?
I haven't
Are the refurbished units more likely to be due to coil whine or a faulty case or just someone not liking the unit? Are the refurbished units of normal quality. I ask because they can be a hell of a price but I don't want to get a subpar unit that just got kicked right through the system without fixing it.
I personally didn't want to gamble since HP is not known for it's customer support. I imagine a lot are returns that are cleaned and repackaged, some are probably units that shipped with something defective and were rebuilt.
This battery works great. A bit expensive, but the first and only one that has been reliable.