It definitely makes clothes less creased so I use it. I only put a small amount in each wash and I'd be surprised if we used more than about 2 bottles a year, because it seems to last forever, so the cost is negligible, particularly as we buy it in Aldi.
We get the unscented one with a picture of a baby on it because, despite DPs appearance as a big burly bloke, he has very delicate skin and normal ones cause irritation.
But what I am confused about is the number of people on here who think it is completely unnecessary and that they are somehow smarter than the sheep who have been duped into using it.