afaik you can cut the spillage from the bung hole (hehe) when you pour your first glass without opening it. The keg should have enough pressure for a first pour, then open the top valve
Angle the glass to pour onto the inside tilted side of the glass. If you do this you'll get less head. Only pour into the liquid in the glass to get a head towards the end.
They still do. It works completely different to this one though, with a tap you clip on top and an integrated CO2 cylinder. As such it lasts a lot longer than these gravity-fed mini kegs and you can store it for a few weeks between uses if you wish.