I've been using FontCreator for a very long time now, and as with all software, I've always been a bit cautious upgrading to the newest version. Although there is a very generous upgrade offer of 120 euros, I'm afraid I'll have trouble using the new version because it's too different and complex. Right now I use the pro version 11-something which was a big improvement from version 6 which I had before that.
Both versions have their quirks, but I've learned to work around that and in the end getting to a point where it seems I know what I'm doing. Often with help from Erwin and Bhikkhu in this forum, I should add

But I'm getting older and older and my adaption to new things is getting harder by the day. And moreover, new versions of software are not always as perfect as the makers claim they are. I still use the Adobe CS5 suite from 15 years ago for example: apart from a load of useless crap, it still does the same as the newest versions my kids are 'lucky' enough to be allowed to have a subscription to for a mere couple of thousand of dollars.
So anyhoo, I couldn't afford to keep buying the upgraded FontCreators every time (I'm not only old, but also poor) and now I'm afraid going from 11pro to 15pro will just be too big of a jump for me to manage, and that I'll just give up type design because of that.