It's crap. Sorry to be so blunt, but it is. It can't hold a candle to Avaya's other PBX products as far as stability, documentation, and overall support from Avaya are concerned.
The new software releases they come out with often introduce more bugs than they fix, creating a "wait and see" atmosphere in regards to upgrading. This goes for both the voicemail and IP Office firmware. I put in one of these when it first came and it was total crap, IP phones didn't even work on the first release. In the end it cost us a high profile client because we could not get the system to perform as expected. It's getting better all of the time but still, I expect better from Avaya having worked on all of their PBX's over the years, and knowing what quality and reliability usually comes out of it.
Reporting software is a joke. It's often cryptic and what little documentation you get is not very helpful. As a a matter of fact, the level of documentation for the whole product line is pretty lacking. Compared with the documentation for other Avaya systems, I can only scratch my head and wonder. Often times on an install I would have to perform tests to see how features work so I could write my own training documentation for the customer because none existed that I deemd good enough. Tech support, at the beginning, was crap also, but has steadily gotten better, though not by much in my book.
I used to put these in, and secretly I thought they were crap but I toed the Avaya line and did my best to make the customer happy, and publicly put faith into this product. Now I maintain an IP Office in an IT Manager position so I have been on both sides of this product.
Avaya bought the IP Office and slapped it's name on it. It doesn't meet the quality of their other sytems yet. It just isn't. The fact that this forum exists is testament to this. Is there a Magix forum? Partner? Definity? No. It isn't needed. Avaya supports all of those products very well tech support-wise and documentation-wise.
I know I am being harsh, but now I have the owner of my company breathing down my neck for results on a system which is halfa**. It is very frustrating. I am no longer the tech who can just "fix and leave", I now have to live with the system. I am just holding my breath and waiting for our company to get big enough to move to an enterprise system.
I will say this. If you are putting it in for a small company with relatively few needs, this system will probably do fine. However, the more applications you try to employ, the more features you try to use, the more problems you run into.
I imagine everyone's gonna pile on me now, but that's my unvarnished opinion, and I have put in 20+ of these, and am currently maintaining one.