Comparison
Here are some comparison pictures of the surface material. As you can see in the photos, the 3XL has a very similar weaving to the Dream Machines DM Pad. It's a bit denser than the HP Omen (which is basically a rebranded SteelSeries QcK), and very different from the QcK Limited. The latter is much smoother to the touch, while the HP Omen is similar, but a bit more rough than the Glorious 3XL.
HP Omen (exact same surface as the standard SteelSeries QcK) vs. Glorious 3XL
Dream Machines DM Pad XL vs. Glorious 3XL
SteelSeries QcK Limited vs. Glorious 3XL
Build Quality
As for the build quality, it's nearly perfect. I did, however, find a small part that sticks out of the stitching along its edge a bit, which I don't think of as a deal breaker. This does not at all cause any performance issues, and I've only found one such part across the huge mouse pad, which is a forgivable error in my book. Apart from this, there are no other issues; the pad's surface is completely even, and there are no bumpy spots or uneven parts anywhere.