I've been doing functional ABS and ASA lately and had a couple very annoying warpage spots. One was a total failure. (We won't talk about the other 3 failures that were wet out-of-the-box Bambu ASA...)
The X1C is definitely nice, but the all aluminum-and-glass side panelling has a sometimes-unwanted side effect: thermal conduction.
The aluminum sides are so conductive that they do not allow the chamber temp to go above 40C, even after a couple hours of heat soaking the build plate at 100C before starting an ABS print.
Enter: One random bath towel. doesn't look like much but just covering the three sides with a thin layer means it's good enough insulation to get the chamber up to 50C now! And the ABS parts look better than ever- every C counts.
It makes all the difference, especially on asa. They're so sensitive to chamber temp and accidental fan use it's actually kinda nuts. I'm really happy with the part's physical strength and behavior of course but it's a very different beast compared to PLA, which will basically still make a successful print even if half of the model isn't even touching the bed lol.
If you can get the chamber to 50-60C it's ideal for those. 40 you can often get away with but on larger parts it is marginal at best.