In my opinion, nothing beats an A4000 as far as overall compatibility, upgrade potential, and features go, especially if it's an A4000T. A3000 is pretty cool too, and you can do pretty much anything with it that you can with A4000 (other than AGA graphics), however it requires a bit more effort to make things work with it, but once you do get everything working, then you can have a system that's just as good as A4000, perhaps even better due to the built-in flicker fixer.
