We’re still waiting to heard from Extralite on what their final plans for 11 speed and the SLX hub. I imagine they’re going to settle on using the Campy shell and non-drive space with a longer shimano free hub body. In this case it shouldn’t take too long to get to market.
Both the Extralite and Alchemy hubs are pretty quiet. I don’t think this is going to be a noticeable difference one way or another.