I am a former user of Family Historian (I am still somehow, I keep switching among them) and this will be my first upgrade regarding RootsMagic.
Curiously I am gradually migrating the other way BUT I fully appreciate every user has different research needs. My current needs are more focused on data mining and the seemingly endless FH data views outstrip the current Rootsmagic offerings to a degree I just cannot see being filled in RM8, however as a long time user I remain ever hopeful.
As regards the current purchase offer if you wishing to stay with Rootsmagic regardless then you will save money by taking advantage of the offer.
I undertook not to publish any comparison videos until end of 2019 where development was meant to be closed but that may well change in 2020.
All in my humble opinion, of course.
Best wishes to all for the holiday season and New Year.