I looooove crochet braids! I have been doing them for years. THe past two years I strayed from them but I'm coming back to them, they are an excellent protective style for me. I'm putting a set back in this weekend or the next because I have natural hair with fine strands and to make my feasible goal of MBL by December or earlier, I have to leave it the heck alone so back to crochet braids I go. My hair responds really well to them and I retain most if not all of the growth/length when I do them regularly. I keep mine in for no more than a month/4 weeks.
Depending on what kind of hair I used, I can wash my hair in them and for obvious reasons, you have easy access to your scalp so washing is a breeze. If I use Marley hair, I don't wash my hair with them in but if the hair is more curly I will.
I plan to rock them all summer because I so want MBL, really, by my birthday 10/27.
YOu can see some pictures of different times I've done crochet braids here:
http://www.agrlcanmac.com/search?q=crochet+braids