The true test for such a tool are usually the edge cases; in my opinion the web is simply too finnicky, and all those well-meaning custom algorithms I've tried fell way short.

I would recommend Ranorex, which combines a comfortable record-replay functionality (which creates real C# code) and a code-first approach and everything in-between. A powerful "spy" assists in creating the most sophisticated locators and turns them into first-class Ranorex objects; a shortcut jumps from code to the repository and back; duplicate elements are detected on the fly.