The GUI is helfull, but still have some very anoying bugs, like to try to save an option and changes unrelated options by itself on the gateway.
Once you learn to overcome those shortcommings, you could use the GUI most of the time.
But still have some times when the GUI gets out of sync with the gateway, and you get faulty status trought the GUI.
At that pointm you still need to pull the old book and do CLI commands to get it back into health.
Overall, after the DX starts working, no trouble to report, unless you start making a lot of changes trought GUI.
I do enjoy the ability to have multiple codecs, and be able to send diferent prefixes on diferent routes.
Things that still does not work:
1) If you have a route to a vendor, and you need to send two diferent prefixes to the SAME I.P. address, it will not do it.
That way, if you have a vendor that requieres you to send a diferent prefix for international and long distance, all to the same I.P., it wil not work.
2)If you need to “call forward” a number to a VOIP destination, like getting a call to a 1800 number via PSTN and need to send it via VOIP to another location, you need to send the whole trunk group (minimun of a whole T1 or E1) to that destination.
If you are on that line of bussines, stick with cisco.
Will not give a “low credit warning”, when you calling card credit is running low.