I realise this thread hasn’t been active for a while, and indeed these questions are most likely answered elsewhere. However, as this is one of the first threads a lot of prospective customers may actually see, before digging around elsewhere, I thought I’d just do an update to clarify on the two main questions raised here.
1: Yes, Gunstar Heroes works with the GG X7.
2: Shining Force definitely does save progress in-game, and I don’t mean by using the save states feature of the X7.
I know these to be true as I was playing both games today. The ED GG X7 is an amazing upgrade over my old ED GG. Not only are the above issues fixed, but even things such as before I couldn’t play H.E.RO. for the SG-1000 due to graphic corruption. But thankfully, as I love that game, it works perfectly with the GG X7.