I've only ever bought one set of Cozee Home, and yes in the depth of winter it was cozy, but I didn't like the feel of the nylony texture tbh, and the way it never sat 'tidily' at the end of the bed. I notice its the same when they do a demo, because of the slippery nature of the 'velvet' fabric its all over the place at the foot of the bed. I gave the set to my s-in-l. I prefer a crisper look.
In this extreme hot weather I've found that my more expensive bedding is way too hot, because the duvet fabric is better quality and therefore thicker. So I invested in a couple of really cheap market stall quality bedding sets where the cotton is really thin and light, and are sooo much better in these hot temperatures. I'm sure Grizzy might agree with this.