Three remarks, though.
1. importing a QIF file the transaction date is translated into the current date. I tried all the options in the import dialog, but none of them had the result I hoped for
2. When filtering transactions on categories, and the criteria is the parent category, I expected also the transactions in the subcategories of that parent category to be filtered. This not being so and seeing the listing of the filtered transactions, I can understand why: the field category (in the line of a transaction with a subcategory) does not contain the name of the parent category.
I think of two options to get this resolved:
a. Both names (name#1: name#2) are in the field Category) like in the Advanced Filter window is shown, or (more complicated I think)
b. A checkbox is added in the Advanced Filter window wether yes or no the subcategories are to be taken into account.
The way to have all transactions of all subcategories filtered is to put all of them in the criteria list; which can be time consuming, depending on the amount of subcategories.
3. In my first post I suggested that when a transfer is deleted from one of the two linked accounts, the transaction should automatically be deleted from the other account. This also was promised

A new suggestion is that a preference can be put with which account visible the file should be opened,and that the transaction(s) with the current date are "in focus",
I need some more time to evaluate but I am already saving some money

Thanks and regards.
Martin