So far as basic machine without expensive addons are concerned, I'd agree that the A3000 is best choice. According to some information I ran across earlier today, the A4000 was actually a prototype for an intended A3000 Plus computer that never got fully developed because of Commodore's business difficulties. As released, the A4000 was not considered by most product reviewers to be superior to the A3000, excepting for inclusion of the AGA chipset and ability to use 64-pin RAM sticks. So far as this point in time, three of three A3000s I've purchased are working just fine....after two attempts, I still don't have a properly running A4000. And, other things considered, I'd say that lack of socketed chips makes the A4000 a poor choice for keeping it alive in the geriatric ward of computerdom.