...Which it should have friggin' come with from the start. I still have no idea what Qidi was smoking providing a plate textured the same on both sides, especially when their previous printers already came with a dual-sided plate. At least now I can make parts that are actually flat on the bottom.
The textured plate was kind of cool for doing large parts with visible flat surfaces, like box lids. But it kind of sucks for doing small mechanical parts.
Kapton sheet optional, but I'd rather replace a 30 cent piece of tape rather than a $48 build plate due to the surface wearing out over time. The massive sheets I used for my old printer (and trimmed down) are almost big enough for the X-Max 3's plate. I think you'd have to try quite hard to print in the last 10mm around the edges anyhow.
I will say this about the whizz-bang side firing build plate fan in these new 3rd gen Qidi printers... It's completely unnecessary, at least with regular PLA. Less than useless. It cools the plate too much, to the point that it can't maintain its surface temperature and your parts will curl and lift off the plate on the side where the fan is. I just disabled it in the slicer. Even printing at pretty high speed -- IIRC the default for regular PLA is 250 mm/sec -- I haven't found any need for the extra cooling, not even with bridges and stuff. Maybe it's more useful when you're printing with Qidi's "Rapido" PLA, which I'm sure as hell not paying for.
Also.
Heh heh heh.
Makers muse has some great videos on the g10 sheets as build surface. Your printer should be running klipper so it would be possible to alter the temp sensor by using a second calibrated temp probe on the build sheet and measuring the resistance of the main temp sensor and writing your own table for it. I did this for some old ntc10k sensors that read way wrong