None of the techniques we have are exact drop in replacements of one another. But they are all techniques that improve quality. I've seen a good QA person in th

None of the techniques we have are exact drop in replacements of one another. But they are all techniques that improve quality. I've seen a good QA person in the right environment be 100x as valuable as all the unit tests and code review combined. Thats why the answer is really heavily dependent on your team and your project. The key though is considering what you aren't doing because you are focusing so heavily on code review.