Up until a while ago I would have said the A1200 because it is so much fun to upgrade. You also have the option of cramming as much as you can in the desktop case, or putting it in a tower and going crazy with mods and upgrades. Now I would have a hard time choosing between the A1200 and the A4000D. I love the way everything fits in the A4000D case, and using Zorro cards is much more satisfying than using PCI cards through a Mediator. For me, the A4000D feels more like an Amiga than an A1200 with PCI cards.
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moto