I'm only giving this 4 stars because it is not truly all-season. It is super fluffy, and extremely soft... it has ties to hold it in place in the duvet-cover which is a must... it is so great to snuggle. But we absolutely MELT under this thing. It's winter here and at least we're saving money on the heating bill because it's now routine to turn the heat down to 60 each night so we don't overheat under this. 
Note: we have it paired with a foam mattress, so it might not be that big of an issue w/ a traditional or hybrid mattress. 
It loses a star because we'll have to find a different cover for the warmer months.