I think the point of the J-CIA is to replace a failing CIA in an actual C64. However, that's not what the title of this HN post is about, so I'm not sure what i

I think the point of the J-CIA is to replace a failing CIA in an actual C64. However, that's not what the title of this HN post is about, so I'm not sure what is going on. Regardless, I think making a replacement CIA is very cool, noble even, and I would be happy to buy one if a CIA in my Commodore failed, if it meant having a useable C64 instead of an unrepairable one. But I do agree with you, that building a completely new C64 out of FPGA replacement parts would feel very weird to me. I wouldn't feel like it's the real thing, even if it behaves exactly like one. The big advantage though, if it's a 100% faithful reproduction, would be that it physically behaves like the real deal, meaning you can plug in actual cartridges, build things that connect to the user port, etc, which are things you can't do on an emulator. For now though, I'm just happy mine still works (even though I kinda want to get a C64C instead of my bread bin).