I read about bamboo viscose and as a hot sleeper, even if my bedroom is 68, I thought I would give this a try. I am a review sort of shopper and the oh wow reviews had me convinced to try them. Something COOLER than COTTON? As I am a cotton person. I'm also one to think that sleeping in just an oversized cotton tee is perfect. Poly gowns seem cool but they are actually hot and have you playing slip and side with your sheets or find yourself awake, covers off, mooning the world. (I know I own them) NOT ANYMORE.... Now let me say I do have a cooling gel mattress, a/c kept very cold, keep a fan on and cool max fiber sheets that go a long way to keeping me cool in my sleep, much better than old mattress, old memory foam, basic sheets etc. which was a sweat fest no matter how cold I made the room, But I want it ALLLLL. I want my sleep experience as lux and restful and COOL as I can get it without being in my birthday suit.Well my first pair arrived. The material almost feels like polyester which I do NOT like. But I figured I would give them a nights test drive. OH WOW. You just lay there and you feel like you have something touching you like the touch of an angel, not of CLOTH. You have to expereinced it. Its better than silk. Its like something is just caressing your body yet its not even there, yet its not see through and you are not having a sliding game with your sheets (especially with an adjustable bed). Now given the country of manufacture and knowing how they think we Americans are all 5'4 and 100 lbs I ordered MANY sizes up. I am glad I did as a tall and larger person as I like Baggy and Roomy, esp to sleep in. The elastic waist runs very loose on me at that size but for sleep I prefer it and I have hips to keep them up and I don't want anything form-fitting and digging in cracks and dents when I curl up for the night. I SLEPT LIKE A COOL BABY! I FELL IN LOVE in one night! I EVEN (and yes you can get away with doing this) loved the bottoms so much...like a very loose capri pant and look nice enough that I paired them with a long modest tee and sandals and wore during a tropical climate hot summer day and no one knew these were jammies and I was SUPER comfortable! LOL They just flow when you move (the bottoms) and do not look like jams. No one was the wiser and in fact I got 2 complments! LOL Go figure! So...I ordered 2 more pair and men's pair in the same material. When you find something amazing, my mother taught me years ago, always buy more than one as you never know when it's going to go away. SO I DID! And I can tell you this....and this is a con though I will not take away any stars for it as I am STILL madly in love and obsessed with this material...and I slept even COOLER than I already had been with all my adjustments. NO MORE cotton tee to bed for me.THE BAD....and yes there is bad-----THE TOPS are TOO SMALL, unflattering and ugly. (but they still feel GREAT to sleep in, minus being TOO SMALL) The pants are GREAT. The tops suffer from the WE THINK ALL AMERICANS are tiny people with short torsos and no busts or pecs. They are not see through, thats the only plus, but still SO UGLY that I have to grab a robe to hide them. Its an unflattering embarrasement to be seen in the set. The shirts need to be made LONGER and roomier to match pant size.The other thing that struck me as strange-I ordered 3 different sets at different but close together times, is that they weigh different. I mean they feel HEAVY in the package, but light on the body, never had that happen to me before. I wish I would have had a scale, but Im pretty good at guessing weights and the one set had to be about 3-4 lbs and another 6 lbs. So Ima guessing they just eyeball these where ever they make them. But each set I got-all ordered in the same size, are really different sizes. Not on tag but the way they wear. One set could EASILY fit like a XL, the other a 2xl. If you are ordering 4x its equivellent to about an american size 1x and top is VERY short and smaller fitting than pants. The pants would work for any body shape, be you all tush, all tummy, all hips or a combo. As long as you have hips they will stay up even if you size up in a major way. And Im talking flowing and not clinging to your legs.Trying the men's wear now and hoping for a better size in tops. I did get the men's pants in this material (they are really unisex and if you are tall you will love them) and they are just as great as the jams.Now all this being said, you will get a weird fit. If you as a woman do not like sleeping with a bra on, which is bad for your health and sleep anyhow, you will find that the tops are tightish-not clingy but tightesh enough to be annoying and due to the material they will show the world the size, shape and position of your "gurls" so if they are suffering the effects of gravity, the whole world will know it. That's not a plus in my book.BUT BUT BUT...this material is heavenly and dreamy (not in your hand-in your hand you think, heavy, poly feel) but once you put them on you will be..AND HOW DID I LIVE WITHOUT THESE) and sleeps very cool...and for that, I will leave the 5 stars, just know that the tops are UUUUGLLLLY and run SMALL and if you order more than one pair you will get different sizes no matter what the label says. Now that I am hooked, like I said I am trying some of their other items in the men's dept and just as good if not BETTER.If you are on the fence, want to sleep cool, relax cool and even pull off wearing these as capris in public (as long as you have a long top to cover the upper part) do not mind giving up fashion above the waist for it (the bottoms are great) then BUY these. DO NOT HESITATE! Your hot body, night sweats etc. will thank you.And now that I have washed one set a couple of times now...I can say that they wash GREAT (I air dry) and there is NO bleeding of darker colors at all even on first wash. WOW nice.HOT SLEEPERS REJOICE! THIS IS IT! (now I want bamboo sheets!) LOL