So,here's another update almost a month later.

Am I still happy with the U1?

Yes.

Am I happy about everything? No.

A few things that tend to get on my nerves.

• The lack of filament cutting is annoying and massively delays changing filaments. Argh.
• The filament roll placement is shit,especially when printing ASA and similar filaments that need to be really dry. (PEBA) Placing them out in the open turned out to be an issue, especially when you use a spool for frequent shorter prints. (E.g. one part of 5h today,another tomorrow,etc.) Especially annoying with the point above which makes simply chucking away four spools time consuming. I migitated that by using a almost closed system of containers - but I suffer from issues with the filament feeders occassionally as the axles for these tend to be an issue.
• ASA has shown mixed results with the improvised hood. (Aka a plastic bin, not fitting properly, holes between it and the printer covered with tape). After looking at it with a thermal camera its clear why: The large ventilation holes on the sides let a lot of air go through (tbf,the current location here is a bit exposed) and the headpad is not heating up fully uniform (but more uniform than the P1S in comparison). So I blame the ventilation holes. Smaller ASA prints are not a problems, larger ones are - especially with more unforgiving filaments. (E.g. Spectrum 275 works well, Black Forest doesn't, Extrudr is somewhat okay) For testing purposes I tried to print with the holes covered and that worked well. But this creates it's own issues - for PLA you need way more ventilation as the fans are FAR less powerful (even though louder) than in the P1S.

BUT I will improve things

• The acrylic glas panes arrived so I will install a proper hood now.
• The additional tempsensor will arrive tomorrow. I want trustworthy independent temperature values in the case before I block
• AND,biggest news, the Panda Breath has arrived and BIQU has published a manual how to install it perfectly into the U1. Will do so soon and expect most of the issues to be solved by that.

So this sounds negative,right? It isn't! I am still very happy and the U1 solves a fuckton of isssues I had with the P1S. Multimaterial,automation, filament tracking, etc. For PLA my print results (with a bit of tuning) are on par with the P1S OR better for things that need support. (As you can use different materials far better than with AMS) And finally having proper clipper back and the options of the extended firmware is nice.

Funny thing: I got two aftermarket print plates from AliE and they are both providing much better grip than the snapmaker original.