I'm a corporate tax lawyer and I use TurboTax. Works like a charm. I check the return after it prints to make sure everything is calculated correctly and that the software didn't screw anything up. I've never had a problem. That said, my personal taxes are relatively simple. If I add layers of complexity over the next few years I'll find a CPA.
I don't trust H&R Block (the McDonald's of tax preparers). I'd be better off doing it myself with the Internal Revenue Code, the Forms and the Instructions, and an abacus.