I just bought and upgraded a 3000 and so far its pretty awesome.
A3000D/16 w/A3640 Rev 3.2
Added
AriadneII Network card for 100 bucks.
Cybervision 64/3D (Amazing card) for 100 bucks.
128MB ZorRam
Can run in 1440x900 matching my LCD display and its crisp and fast.
I seem to have much more challenges getting games and demos to like the 3000 then my A2000.
Get a 4000 if you need AGA, otherwise Mechy sold me a SCSI Compact Flash that is AMAZING! with LUN support I can plug all kinds of cards into it simultaneously.