We have used several kinds, and each worked well (for a while.) I think it depends on your water, your kiddo, etc. Rockin Green was good, so was Allens. Nellies was okay. We are using Tide F&C now, because we get really bad ammonia build-up, and Tide ended up being the only thing that worked really well. You can get sample sizes of a lot of the brands though, so you can see what works best for you. Unfortunately, I think there is a lot of trial and error.
We use Charlie's Soap and occasionally I will wash them with Dawn to help strip off any detergent build up we may get or any build up from Non CD safe rash creams that the girls at daycare keep using mistakenly.
Re: cd mamas-
BFP#1 "Watermelon" born 3/2011
BFP#2 "Pumpkin" 7/14/12 ~ EDD 3/23/13 ~ Natural M/C 8/3/12 @ 7 weeks
BFP#3 "Pineapple" born 4/2013
BFP#4 "Grapefruit" EDD 3/29/16