It may seem hard to get excited about memory locks but they save an enormous amount of time when setting up a drum kit. You know what height your floor tom needs to be, and with a set of these handy locks no time is wasted in ensuring it's right where you want it.
They probably seem a bit pricey (about £5 each - and you need 3 for a floor tom) for what they are but once you have them they just need fitting once and you don't have to worry about them again.
Get them, then forget them.