Jaques: Well, regarding raising ACA500 2MB limit, all of this is what Jens proposes for his coming cards, except that you wouldn't have to order and solder extra parts...
So maybe it won't meet with as much resistance as expected in the end. If you can't afford the top end model this month, you can still order it while there are cards left in stock, and upgrade with a digital download next month. Meanwhile, you can use it and check that it works, and will find out if you need the upgrade or if it's fine for your use.
I eyeballed the unlocking of existing RAM especially, but the "scheme" is growing on me.
In other words, if Jens had made the ACA500 cards with this method, if 4MB was possible the 4MB would already be there and we could all have upgraded by now