I really like the king size pillow. It is easy to manipulate to how I want it for any particular sleep, i.e., squishy enough. The standard pillow seems more dense and less malleable, but it IS a better proper-upper. I have 2 of each, because I am spoiled.
I loved this pillow when I first received it, helped me sleep and incredibly comfortable! However, over time, this pillow has "deteriorated" faster than any of my previous pillows. The outside pillow hasn't really held up, so the pillow overall is now incredibly flat and somewhat hard. I followed instructions on taking care of the pillow, and yet I am disappointed that the quality did not last! In terms of investment, while the quality of a cheaper pillow may not be as good as a Casper to start, the quality is longer lasting than my experience with the Casper which started off great and now is anything but.
After reading all the reviews on this pillow I was real excited to order one and give it a try. I am very picky with pillows so I completed a lot of research before ordering one. Unfortunately I am not impressed with this pillow. After a couple months of use and every day fluffing like they suggest, the pillow becomes very flat during a night's sleep. I would wake up and my head flattens the middle of the pillow and the fluff goes to the sides, which is very uncomfortable. I would not recommend this pillow especially at the price point. I actually went back to using the pillow I had before my Casper one because it does not flatten out as much as the Casper one. I am now on the search for a new pillow.
I like the Casper pillows quite a lot. They are very lofty and cozy and soft. One thing, they do run a little hot- I would have loved a more cooling fabric on the outside case. But covering it with my own pillowcase it is dreamy.