One warning about the X-Arcade PCB. There are various 5-pin connectors, and each of these contain 4 components and a ground. (Eg: P1 Up, Down, Left, Right, Ground).
This is fine if you want to wire the PCB directly to your control panel, and be done with it. However, you cannot use the ground wire from one group, with the signal from any other group (this results in interesting random results), which means you CANNOT build a panel with a single ground to all the controls - you have to do this in groups.
I am currently building a JAMMA-spec cabinet, that can support both original Arcade Game PCB's as well as MAME (via XBox), and I just ordered the JPac (and have to return my X-Arcade because it cannot do what I need).