The Aireolux 500TC Sateen Lyocell Cotton Sheet Set is extremely soft and breathable which is great for memory foam mattresses. I sleep very hot due to our memory foam mattress which my partner needs after back surgery. The sheets for remain cool to the touch all night long which brings welcome relief from hot sweaty sleepless nights. I have washed the sheets several times and I've had no issues with loose threads, pilling or seams coming undone.