Everyone else beat me to it . . .
I would like to order everything one place just to make it easier. How is there sales support. I will definitely have questions (what I need to buy to make everything work..i.e. wiring harness, mounting plates etc...)
Support is top notch from either GGG or Ultimarc. RandyT from GGG is a member and active on the forums here.
Really you don't need mounting plates, the TT2 mounts in the same hole as a pushbutton. You might want to get some quick-disconnects from Randy - not sure if he sells wiring as well, but Radio Shack would have that as well.
GGG sells the GP-Wiz (looks like a gamepad to the PC and is USB) and the KeyWiz (looks like a keyboard to the PC and is
USB PS/2).
For a desktop CP, I would consider the GP-Wiz - allows you to mount a hub in the panel, plug the GP-Wiz and TT2 into that and have one cable to connect to your PC. Non-MAME games will need some configuration to work with the gamepad, but not a big issue.
For a full arcade cab, I recommend the KeyWiz - better compatibility with other non-MAME emulators.
Note that the TT2 interface will also support a trackball down the line if you decide to add one.