A1 looks to be more expensive and incompatible with the 1000's of older titles. The C1 is cheaper and plays the old titles.
I think they have 2 completely different buisiness plans.
I grew up on the c64 at the time it was top dog, I have alot of good memories from those days. But since I have a working c64 and 128 with drives and monitor I dont see a point in buying a C1.
I didnt have an amiga when they were out since I jumped from a c64 to a 286 PC but I have a A500 now and enjoy the games on it. I dont see the point of buying a A1 because all I want to do is play the old games which I do now easily on the original hardware or the PC emulator.
So from my standpoint if I was to buy either unit it would be the C1.