I bought these when my other cotton sheets didn't fit my new mattress and topper and needed extra deep sheets.  These are advertised as fitting mattresses up to 20" deep and not a hair over.  They ARE soft and of a heavier weight which I prefer but the only drawback for me is that the elastic, which goes all the way around (a plus), is thin and not very strong which I feel results in a looser fit.  I washed these sheets twice in warm water under the heavy soiled setting to get starch out and to soften more and they held up just fine.  They are just a tad scratchy on the face but I'm sure that will soften more over time as with my other 100% cottons.