A little late to the party but I'll put my experience in.
I managed to find the SheaM cowash a few weeks ago and it's definitely lighter than the AIA cowash. It's got good slip for me, more than most, and I like the feel of it on my hair better than the AIA. I definitely don't need a L/I when I use it. I used to like the Bioinfusion rosemary mint but it gave me buildup and now that I think about it that was before I discovered that I actually can clarify poo without problems. *gasp*
Yep evil mod-CG here, come to the dark side.