Martin's probably at Matamp for the day but I can fill you in on the 2x12.
It's a semi-open back design. Mainly closed but with a two inch port running the width of the cab. That stops the tone getting too 'boxy'. The cab is made from 1/2inch birch ply and the speaker of choice is the Hot 100. It's a really great speaker, and a bargain too. I chose it over V30s, G12Hs, a mixture of the two, G12T-75s etc. I've tried them all in my cab.
Tonally the cab is big, punchy and thick sounding. Not quite a 4x12, but it's in a pretty close ball park. So you've got the size/weight of a 2x12 punching close to a 4x12, which is a nice place to be. An added advantage of the Hot 100s is that they're a fairly light speaker, which helps with the portability.
Mine has a top handle and two side handles, Martin's just a top handle. Tolex covers, corners, grille cloth etc are all customisable to your preference. Some coverings can cost more than others though, so this will affect the price. Your choice of speakers can also be fitted of course, which again affects the price.
I should be a salesman ;)
