about me, the only advantage to take a Shark, is keeping your Amiga1200 and continuing using it for Old chipset dpendent programs.
You never will be able to use old progs with AOS4, so you will have something like 2 computers on the same tower.
In this situation, the best thing to do is keeping your hold amiga for nostalgic software and buying a new computer "PEGASOS or amiga1" for serius progs.
Pegasos is realy a sweet,it is very stable lke a rock, 100% AmigaOS 3.0 compatible, not a lot expensive, fun like all amigas.
Amiga1 would be nice to, but I need see, to belive.
have fun
Serge in pegasos land