For me who moves a lot in my sleep, I was tired of waking up with bedsheets completely defeated! It even happened to find myself on the mattress cover. With fixed bed linen, bed rest impeccably well. In the morning, it seems that the fitted sheet has just been because it remains perfectly taut. The only negative is that the sheets fixed installation is not very convenient ..... I was forced to completely turn my mattress to install them. Purchase very satisfactory, do not hesitate!