Newbie to this forum but Oldie to the Bass, so this is my first post. Just came back from the local music store, where I test-drove the G-K MB115: pretty nice little combo for the money ($399.00 OTD). It seems to hit the sweetspot between my three Bass Amp Criteria: Good, Light and Cheap. And since, this year, I have both moved to a house at the bottom of a 50-step staircase and turned 60, the Light part is now the priority. The other two are still important, but they don't mean a thing if I can't wrestle it down (and more importantly, up) the Permanent Stairmaster. The store is kind enough to hold it for a day, so I can sleep on it. Before I pull the trigger, though, does anyone know: 1) Just what are the differences are between the "Mark I" and "Mark II" models? and 2) How can I tell the two models apart? I would like to have 'this year's model' if at all possible. Thanks for any information you can impart.