Brooklinen makes some great sets, but quite a lot are returned cuz of shrinkage or the fabric getting scratchy over time (major ick) For cotton-linen blends, I’d recommend California Design Den or Sijo. Parachute has a nice relaxed look but can be high maintenance and tends to wrinkle heavily. Coyuchi is solid if you want something organic, but their king sizes tend to run a bit snug after a few washes. I’ve seen the most consistent feedback on California Design Den (linking it cuz its a little nicher ig). Its super soft out of the package and holds up well, full shade to brooklinen. All three are reasonably priced and feel higher-end than some of the bigger brand offerings in the same bracket. They also tend to last longer before you see pilling or thread fray. For washing, I usually suggest cold water, gentle detergent, and low tumble dry or hang dry if possible. Avoid fabric softeners or bleach both mess with the finish. If you like a crisper look, toss in a dryer ball or two to soften without chemicals More on reddit.com

https://a.co/d/0N7pKOH I love this duvet cover. More on reddit.com

The duvet itself or a duvet cover? For the duvet itself, I've only ever spent a modest amount on them, I spend more on the covers. Personally, I'm not one who sleeps under duvets anyway; I usually take them off my bed before I go to sleep. I do love them for decorative purposes and have generally used the same trick that they use in design spaces which show off bedding setups: I buy two moderately-priced ones and double stuff my duvet cover. Makes it look super plush and luxurious. Super soft to lay on. I don't sleep under them anyway so I care more about the visual element. More on reddit.com

I feel like the super king would be too big. More on reddit.com