Its not hot at all. I rate it higher than the tempur which does get hot. I think there are two half price sales a year. I remember buying it in November and it was full price, I waited a week and they went on sale. Checked back xmas time and price had gone back up.
Was it Ergoflex? Because I don't have that problem at all and that's with a 13.5 tog duvet.
Also, check out Tempur results on Which? crucified ? Don't waste your cash folks?
Don't buy a memory foam mattress unless you enjoy being cooked in your own juice every night, hotter than hades?
I think it's pretty much a permanent 'sale', I was not sure at first because I tried a foam mattress topper and didn't like it, it was sleeping on a Tempur mattress that convinced me it was a good choice. It'll last longer and it wont wear out like normal spring mattress's do.