As I have been pushing myself to fully adopt GTD, I have just started using IQTELL since reading this thread.
So far, it appears to have a true GTD orientation and I am finding it easy to integrate my tasks and projects. I have been very fickle in the "system" I use, bouncing from RTM, to Toodledo, to Outlook and back. IQTELL is the first one where I felt comfortable and actually looked forward to setting up my work.
Thanks for the thread!