In my readings about baby bedding, I came across these two variations of matress pads which seem pretty slick. Instead of placing the pad between the sheet and the matress (which normally requires pulling up a messy sheet from all four corners and replacing it with a clean one in the middle of the night) these pads are right on top or actually integrated into the bedsheets and can be easily changed. Do any recent mommies have knowledge/experience with either QuickZip crib sheets or the Ultimate Matress Pad?