Please allow me to add to the positive reviews!A number of years ago, Mesa produced a vertical 2x12 cab with open back in the top half (C90 ?), and a sealed bottom half (EVM12L). All I have ever read was positive.
I have an old K&K Audio vertical 2x12 1/2 open and 1/2 closed that sounds great! Pre-rola G12H30 in the open half on top and a G12-65 on the closed bottom. Fat, crisp and punchy all in one.