If you get the micros there are some things that you need to beware of:
Make sure that your hair is READY for braids! What I mean is that you need to get your hair deep conditioned and treated with maybe hot oil. Get a good trim also. BRAIDING IS VERY STRESSFUL TO HAIR.
They are braided very tight, especially if you go to the African shops. This can lead to breakage at the roots!!
Secondly you need to keep your hair moisturized with some braid moisturizing products. My hair was very dry and brittle after so it took me awhile to restore moisture.
Be careful of who takes them out because they cause breakage.
Don't let the braids stay in more than 3 mos. Let your hair rest.
I sure hope this helps, good luck.