The Address Book Reloaded 3.0.4 is getting closer to being a stable release. Unfortunately we added duplicate email checks that broke the installer. V346 was retracted until we can fix it. But I expect the release candidate to be out end of February.
Factory objects to allow replacing classes should make it into the release too, so that almost no change of existing code is needed to make big changes on the system.
The new DB structure seems to be a success and gzm0's OO design performs well.
Try the DEMO of the most recent repository version at our homepage: http://tab-2.sourceforge.net/
Please file bug reports if something fails!