I am also 3com certified and do a lot of work with the 3Com nbx, I really love what asterisk and freepbx are doing.
One thing I do miss from 3Com is the ability to test my dialplan BEFORE putting the system into production.
On the 3com, you can go to a test page and it shows a list of all T1 channels, pots lines, etc and all extensions.
You can then select any chanel, line, or extension, select the time of day and day of week and then type in the number to be dialed.
The system then checks this against the dialplan to make sure,
1. that that channel/line/ext can make that call
2. that time restrictions do not block that call, and
3. it shows what channel/line the call would go out on and what digits were to be outpulsed.
here is a screenshot of the page I am describing.
http://levonandjackie.com/test/test.jpg
