Having a group of a few best friends is one of the best things in the world! It's like having sisters except you don't have any awkward sibling memories or any kind of sibling rivalry. The bond between best friends is one of the best kinds of bonds you can have with someone. It's like you've known each other forever. Your family is their family and vice versa; you call their parents yours, you pick on their siblings, and you feel at home when you're with them.
Best friends make you a better person. Best friends are always there whether you need them or not; it's one of the best things in the world to always have people to go to, to vent to, to go to for advice, to cry with, to laugh with, to make memories with, and to experience life with. Best friends are those people you can tell your absolute deepest secret to, and they will take it to the grave. Best friends are the people who work to prevent from making really stupid decisions but are also there for you after you make those really stupid decisions.
Having more than one best friend means that each will most likely be different so every time you go to your group of friends for advice you'll hear something different. It is also really cool when you have certain things in common with each best friend. Having a few best friends means always having people to rely on and trust. It makes life better, more fun, and easier. It also makes life much more worth all of the crap you may face at times.
Those few best friends are an outlet when things get hard and a lifesaver when all you could use is someone to talk to.