The PGM system was really quite bizarre, and even today neither of these games are emulated. Since I happened to have a rare board that no one could download and play for themselves, I made a bunch of screenshots.
And, well, here they are:
The game itself really wasn't very good. Dodonpachi is normally a game series made by Cave, a Japanese developer. For whatever reason this one was released by IGS, the Taiwanese company that made the PGM board. Stranger still, Cave went on to release a handful of games using the PGM system, but as single boards rather than the cool red carts normally seen on the PGM.
So, did Cave sell off the name to PGM or did they program it themselves? My guess is whichever way that worked they were given a license to the PGM hardware for their own games in exchange. It seems to have worked out well, in any case.
iPhone Dodonpachi Resurrection review
System16.com's page on the PGM hardware