I would choose the Surface Pro 3. As an attorney, a large tablet with the flexibility of becoming an almost fully functional desktop would be a huge bonus. I could work on my cases in the office with it, take it to court and use the stylus to take notes and mark up PDFs of legal documents as I talk to other attorneys, judges, my clients, etc., plus I could take it from the office to the conference room for note taking as I interview clients or organize legal strategies for a case. And it still has the added bonus of serving as a media consumption device during my down time or my off time.