I use a Dell XPS 15 9560 (2018 model), and so far I haven't had any unusual fan noise issues.
Overall solid experience - just watch out for the HiDPI screen shenanigans if you plan to get it, as it will affect what desktop environments you should choose. Global display scaling is an absolute must, unless you want to squint at everything (unfortunately, a lot of kernel and GRUB messages will be very small since they aren't affected by that global scaling - not quite sure if there's a workaround)
Update: Linux console - ArchWiki contains the info to change the font in consoles (tty and Plymouth boot screen). I'm using ter-132 and it works really well. No more squinting
Plugging in external monitors can also be a pain too because of the whole resolution thing. Works for the most part, but then sometimes it glitches out and you get a portion of your external monitor on your main display, particularly when extending rather than unifying outputs. If you just get the FHD screen though, these problems shouldn't affect you (plus, much better battery life with that one lol)
The only other thing to point out is that sometimes SDDM will not start, most likely the dual graphics card setup issue. I still haven't managed to fix this, but overall it's not a huge dealbreaker.
Also, things to point out if you're serious about the XPS:
Dell's build quality can be questionable (I've had 2 Dell laptops so far and both came with some sort of defect), so make sure to check for anything defective as soon as you get it. Mine had a dead SD card slot from the factory, and I only realised after the warranty was over.
if you plan to do anything intensive on it, undervolting is a must. It throttles way too early otherwise, and i don't understand why Dell ships it like this because it basically becomes unusable. I think on the newer models it's locked due to the Plundervolt vulnerability, so you will need to directly edit the BIOS. That will require lots of patience and squinting, or a magnifying glass because the text is tiny as. The thing responsible for the locking of undervolting/overclocking is Intel ME, which can't be downgraded.
There's Arch Wiki pages dedicated to this laptop. Here's the general one: Dell XPS 15 - ArchWiki
There are also pages for specific models if you're looking at a particular one (eg. 9560), but I don't think there's anything for the latest.
Whew, that was a long post lol, but I hope it's useful and informative. It can be a problem child at times but overall it's a solid laptop, and on Garuda there aren't too many problems that stem directly from the laptop. ^^