What gem/plugin should I use?
I've always enjoyed shoulda.
How time consuming TDD really is?
The reason I've always favored TDD development is that it focuses how I will implement a specific piece of code. I have an anecdotal feeling that whenever I adhere more strongly to TDD principles I spend less time reworking later. The amount of time spent is all in how well you write unit tests though. If the unit tests don't capture the expected behavior, all the time spent on them is wasted.
