Hi - I do use Gramps and have done so now for past 18 months. The more I use it the more I like it. It has the option of using "Gramplets" which are basically add on scripts which allow you to produce a myriad of reports and what have you. It is all totally free and is very actively developed by the Open Source community. I also have my copy of Legacy Family Tree that I have maintained but more and more I use Gramps as it is so fast and capable. I also use Linux operating system most of the time instead of Windows and it operates on that as well just as good as any other program. Hope this is of some help to you.
Regards.. Phil Hill - Perth, Western Australia