From a work science standpoint I can see the benefit of separation. Search must be working through both at the same time if I want to.
What makes the TABS difficult for me now is that they disappear when I change between work and private account. In General I like them thous, its much cleaner then cluttering everything with double clicked extra windows for multiple notes. I love the TABS.
Positive is that the is a note move between the private and business accounts again and not the copy and delete workaround. I did not believe myself first how often I move notes between the two.
A real cool feature would be the scrivener style doubleview single window that allow you to see two notes in the main window side by side and have one of them active. I find this one of the main attractive features of the software.