Your talking about Office2 HD right? I researched this pretty thoroughly about 2 months ago and at that time it was the only document app on the ipad that could track changes in edit (and not just show tracked changes). I have used it a couple of times and it has worked fine and the changes and document formatting show up as they should on MS word.
If you are editing with track changes, you probably need clean compatibility with MS Word. Office 2 HD is as good as the others in this respect but I have not done that much testing since its still too much of an unknown and will try to do light changes on a RDC until I have done a few more things with the app and have more confidence...still it is promising so far.
The other thing is that it is rumored the MS has already developed an MS Office suite for the ipad but are holding back because they are not sure of the pricing point and how much it will impact sales of their new Surface tablet. This is really their only real ace up their sleeve but they have a huge problem in that they risk opening up competition that is currently non-existent if they dont move fast and dont price competitively. Currently, MS Office is not cheap. 2-3 hundred dollars for one license compared to 20-30 dollars for most office app suites. No one, not even companies, will be able to justify this purchase. These products tend to trend in cascades and charging 10X will pretty much destroy the mini monopoly MS has on office products. OTOH, offering the products at competitive pricing will all but kill their desktop sales unless they drop those prices as well.
Ultimately, I think MS will be forced to sell its Office apps at competitive pricing for the ipad since, although they lose profit margin, they retain their dominant market position.
