Here are a few points I want to highlight.
On many of my implementations, I like offering the customer the option to use account categories. Management Reporter has made mapping to these categories much easier than Frx. In Frx, you have numbers as the linked value, not the actual category name like in Management Reporter. If you do build your reports using categories, it makes it easier to keep the reports up to date, as new GL account numbers require a category to be added.