I'm especially interested in your statement: "Our experience with Office Integration tool is tragic. We abandoned it but would still like to get metadata on documents..."
What have you seen for this specifically? We have it on our list to (attempt to) implement this year.
From day 1 with Windchill, we've invested extra in Document Collaboration Option, in order to be able to apply watermarking to Word Doc's and be able to treat them like Drawings in this regard. We also would also very much like to get metadata on documents, and this is the (only) attraction of Office Integration.
We experienced an array of problems related to MSI instability, MSI non-function, some serious slowdown of office app launch and sometimes even complete failure to launch office apps. Most of our efforts to get it working were with 9.1M030 XP32 and office 2003. I must admit we did not pursue these problems with PTC. There may be a simple explanation. At the time we had higher priorities and the functionality gain was not high enough.
Things have moved on now with new Windchill builds, Windows 7 and Office 2007/2010. So perhaps its not even relevant. I'm sure you have your eye on the latest related compatibilities.
One thing that bugged us was an inability to report windchill attributes in .ppt files 2003 without some custom scripting. I'd say this is more of an Office issue though.
Sorry I don't have much more to add, it's perhaps off topic anyway.