Vantaggi
Just finished my 3rd year @ Appirio. Overall, it has been a very positive experience. I enjoy working with very dedicated and capable people. The projects are diverse so you can get a lot of exposure to a lot of different industries. Appirio is by far the most transparent company that I have every worked for which is refreshing. The CEO will address any question that is raised head on and tell you what they are doing about it, even if the question is not quite appropriate for the forum. Appirio has had a fair amount of turnover recently but I think things are stabilizing now. Of the people I know that left, most were because there were other opportunities to be involved at startup orgs, not because the culture at Appirio was bad (my experience only).
Svantaggi
The Wipro acquisition has been a bit of an unknown. Unfortunately, many of the experiences I have had with Wipro within Appirio reflect the "low cost, squeeze-prices-down" mentality that Wipro is known for which is not why I came to (and stay at) Appirio. I am holding my breath that they keep Appirio separate from Wipro as they have and let us do our thing in peace.