Then go for itI went from a regular HDD to a fusion drive to an SSD, and several times per day it was like being back on the HDD with the fusion drive, whereas the difference moving from a fusion drive to a pure SSD solution was like night and day. But I mean, this is based on my personal usage pattern so I am in no way saying you'll experience the same thing.
Thanks! Honestly I'm quite still uncertain but at the end I will go for the FD.
What do you use the iMac for so that you've noticed so much the difference?