I've written about some of the more interesting cases I've done:
Cullather. A case about a newer Affordable Care Act tax.
Klimov. A curious New York City residency audit.
Merdjanoff. An interesting international tax case.
Sauer. There was Red Bull involved...
Kosofsky. Why punctuation matters...
Tax Court Success Rate
Besides these, I keep track of my success rate in Tax Court. These are petitions filed in response to a notice of deficiency.
Average reduction per case (dollar amount): $65,782
Average reduction per case (percentage): 76%
Cases which saw some reduction (percentage): 96%
This table of course only represents one type of dispute, and it doesn't include cases that were resolved with the IRS without the need to file a petition. (which is most of them) It also doesn't include cases where clients withdrew or otherwise canceled services. Nonetheless, it gives a general idea of what to expect.