I haven't been before, but I'm probably going along tomorrow, sahbear.

Manducca can do a couple of things that the Ergo cannot (or at least the older Ergos couldn't do - cross over straps at the back for one), but the two have similar structure. Manducca was apparently designed by someone originally from Ergo.

I'd try both and see which you prefer - the meet might be a good opportunity.