Is anyone using an airlock/vacuum system on their Ikelite housing? If so, what are your thoughts? I have searched the Ikelite website and dont see where they offer one, so I guess it would have to be an aftermarket purchase and install. From what I have read, it sound like a pretty sensible item to have. I found that it is standard on the Nauticam housing (for my camera) but it is over double the price of the Ikelite housing. I am wavering between the Ikelite and the Nauticam housing. I thought maybe installing the airlock/vacuum system on the Ikelite as a possibility too.