This mattress is very comfortable and I really like that I can't tell when my husband moves around or gets in and out of bed through the night. He feels the same :)
So far I'm loving the mattress. Going from some random $100 full size memory foam to a Tuft & Needle Cal King is like night and day. Due to work I'm still only getting 5-6 hours of sleep, but it feels like a deeper sleep and I'm more well rested when I wake up.
No flame retardants, mostly. Inexpensive compared to other mattresses. Delivered to my door. Simple checkout process, free shipping... oh, and a very comfortable mattress. Nothing bad to say about any part of the process. But I didn't have to contact customer service. So I dont know that aspect of it.