Marshall Lead 12 5005 mk1 vs mk2 circuit differences and comparison

Here's a quick shootout between two versions of the Marshall Lead 12 5005. My guitar is going in the two amps at the same volume (thanks to the Boss LS-2), and I'm switching the outputs of the amps to the same speaker with the little red and blue "sexy switch". Light on on the switcher = mark 1 (on the left) Light off on the switcher = mark 2 (on the right) I'll post a more detailed description later on, in the meantime sorry about my english and my playing and don't hesitate to ask your questions in the comments.