Okay, so I finally caved and bought these bamboo viscose sheets after seeing all the hype. Here's my real-deal review after sleeping on them for a month.
First off - the softness is LEGIT. Like, 'why did I ever sleep on cotton?' levels of soft. They've got this silky feel that makes getting into bed feel fancy, but not so slippery that you're wrestling with the sheets all night.
The cooling claim? Mostly true! I'm usually a human furnace at night, but these actually help. Not ice-cold magic, but definitely cooler than my old sheets. My partner (who runs even hotter) agrees they make a difference.
Fit is solid - our 14" mattress has no issues with the deep pockets. Though fair warning: they do wrinkle like crazy after washing. I've embraced the 'lived-in' look because ironing sheets is where I draw the line at adulthood.
Biggest surprise? Pet hair doesn't stick as bad as other sheets we've tried. Our two cats seem to approve too - they've claimed one pillowcase as their new napping spot.
Would I buy again? Yeah, probably. They're not perfect (looking at you, weird seam placement), but for the price and comfort combo, they're staying on our bed for now.