I begged for one for christmas one year. Literally all I wanted.
So I get it, go to my room and plug it in and wait.
Well it was taking a long ass time to warm up.
So... I shook it. Figured that would mix it up a bit.
Didn't work.
Only now there's this big chunk of the stuff floating in the middle with the heating element sticking out.
So, I panicked, unplugged it, put it back in the box, told my parents it was defective, and returned it for a replacement, which I was very careful not to shake.
Couldn't really enjoy it though due to all the psychological baggage that came with the experience and the fact that it took a really long time to heat up.