I've been using the Sealy All Night Cooling Pillow for a little over a week now and it doesn't seem to have flattened at all. The pillow is super plush and on the firm side, so I expected it to flatten out a bit from day 1, but so far it hasn't. This could be good or bad, depending on how thick you like your pillow. 

As for the cooling effect... I don't notice it. I live in FL where it's hot all the time, so a cooling pillow sounded great. However, I really don't notice any difference in temperature between this pillow and my old pillow. Maybe it's the pillow case that feels warm, maybe it's the pillow? I don't know. It just feels like a normal temperature to me -- definitely doesn't trap in any extra heat compared to other pillows though.

Regardless, if you're looking for a shockingly durable pillow that won't go flat, this would be a great choice. The picture is of the pillow today, after a little more than a week of use.