Good QA process is always part of a wider Continuous Integration (CI) process. The primary benefit of CI is not speed, but consistency. Continuous Integration provides a safety valve for quality as early as possible in the development process. Verifying your work regularly with an automated build helps catch bugs quickly, before they can snowball into larger issues. As a result, less time needs to be spent on testing overall. Each release, whether manual or automated, should be automatically run and reported on.
Maintaining an automated test suite is the best option for developing a scalable CI process. Human-based testing often can’t scale to your needs, so integration may become a bottleneck. Further, if things aren't automated, they'll be missed.