It would be nice to know more about their portfolio, such as the companies that have gotten funding from them and achieved a liquidity event.
http://news.ycombinator.com/item?id=40412
the news.yc user "blored" got funding from them. And blored's profile (http://news.ycombinator.com/user?id=blored) suggests that their site is
Edit: oh, you said "AND achieved a liquidity event". Yeah, don't know.
The best thing about Tandem is that they are made up of good people. The venture raising part was very painless, directly a result of Sunil's professionalism.