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you're quite brake ordering one. FYI, you can buy USB endoscopes for super cheap on alix, in your shoes, i'd 100% get one and make a conscious effort to inspect all tubes of the frame i receive, because composites manufacturing isnt trivial, especially now that we all want light frames again. If your layers aren't compacted properly (should be much less of a problem now that EPS / latex moulding is very widely used), or if you're straight up missing material in key areas, then bad things can happen.
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not to worry, i have ordered an endoscope already and intend to thoroughly check the frame once i have it in my hands. I will share here if i find any issues.

But i don't think it's brave of me to order one - the risk, at least in my view, is fairly small. And that, for me, is okay, especially given the prices we're discussing.
And if there's any issues, i have all winter to get this sorted with LC ...

Can anyone explain to me what Z3 quality is and all the other qualities?

Do all other sellers also use this notation?

To properly answer your question: this notion of different quality control levels in the context of Lightcarbon came out of a discussion Hambini had with LC people at Eurobike 2024. Hambini explains it in his blog here: https://www.hambini.com/bike-frame-manufacturing-standards/

Here's the main summary of the qc levels:

not sure if this is new (it is to me). LC is promoting the LCR017-D with '"Z3" Level Quality' on their homepage. This at least matches what Jim and Gavin have mentioned in the email correspondence I had with them.
Looks like people should then also be able to refer to that in case of any issues with the QC

even then, the restaurant should be given the opportunity to make it right.

There is a lot of fuss being made here about one frame. i think there will be QC issues but as long as the companies deal with it in the right way (in the end the customer should be satisfied with what they got), for me this is acceptable.
After all, to expect flawless QC at a fraction of the price for western brands is quite unrealistic.

On a different note: does anybody have the exact clearance for the fork and seat stays? Im wondering if 32 mm really is the limit or if i can push it a couple more mm if necessary.

After reading every post in this thread and falling in love with some of your bikes, I decided to order this frame two weeks ago. But now you're making me doubt—will I receive a bad frame just because I ordered it before the Hambini video and didn't specify the code? 

In my communication with Lightcarbon i addressed this topic. Their reply was:

"No problem, we can get you the frame with Quality standard Z3 (actually this model are all produced in Quality standard Z3, what Hambini got is just a regular one from our mass production)."

Looks like there was no special treatment for Hambini, which however doesn't mean that issues with QC can't still happen ...