I don't think that such "versus" approach is a good one. I will try to explain why...
Automated vs manual testing?
If you can automate all your tests, will be amazing! But with which cost? So, I belive that we can apply a kind of Pareto principle (80/20) and find the test that will bring more value if they are automatized. Therefore we can focus on them and delivery the best results fast and with low costs.
Unit testing & functional testing?
I do not think you can achieve great results with only one of them. You need both, maybe one more than other. This decision need to be a case by case analysis.
What's your preferred set-up of continuous testing environment?
IBM has many tool to support continuous testing, you can go here and check https://developer.ibm.com/testing/. Again, there is no "one-fit-all" solution, maybe my preferred set-up will be the worst to another person. Maybe, you even do not need tools at the first place, but change your culture will make achieve good results from countinuous testing.
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