Basically, how much does it hurt. Comfort is more than simply having a small diameter shaft. The quality of the grinding makes a big difference. Ease of Use . We all want our kids to do their own testing.
Some products are easier for little hands to use than others.
This mostly applies to the lancing devices, but some lancets are more troublesome than others. When you're done with the stick, you've got to dispose of the lancet. Some are completely self-contained and require no recapping. When applied to lancing devices, factors examined include the ability to recock with exposing the lancet. No matter how wonderful one brand is compared to another, if you can't afford it, it doesn't do you any good.