Versatility. The GRIP-N-PULL bullet pullers can be used for multiple calibers. For example, the Standard Rifle GRIP-N-PULL pulls bullets of ALL of these calibers: 17, 20, 22, 24, 25, 26, 27, 28 and 30. Bottom line: A single GRIP-N-PULL takes the place of several collets, faster, easier and cheaper.
Durability. GRIP-N-PULL bullet pullers are made of 1/4" heavy-duty #30 stainless steel.
Usability. There's no contest, really... GRIP-N-PULL cuts reloading time and completely eliminates the mess.