Thanks for the replies.
Funnily enough, my current iMac has Fusion drive and I never had any issues. That's why I was really surprised when I saw many posts on this forum with the advice to avoid Fusion drives. Maybe earlier Fusions drives are better than the current ones, I dunno
Is Halswell i7 significantly better than IvyBridge i7?
I suppose that 4gb of video is always better than 2gb even though I don't do any video editing or play games