Out of the box, the A3000 is IMHO better. Built in flicker fixer, scsi, etc. And other nice things like socketed/upgradable/repairable chips, 030 fallback (not so needed anymore).
sure is my a4000 ls a cheaply made badly thought out machine scusi on my a3000 is much better than ide on the 4000 plus you can conect more devices than with ide.