So, having had the Kilner jar idea shot down, I've invested in s pair of 5L easykegs. Has anyone here primed beer in these? I'm going to be racking to a pressure barrel with sugar added, then bottling/legging from there. My main question is whether these might require more sugar, and how much headspace to leave in the easykegs (indeed, how do I tell how much headspace there is?). Finally, do i replace the bung provided with the pressure-release plug at this stage?