This question risks being closed because it's basically inviting people to share their opinions. Also, the reality is that the answer to this question may very well be different for different users.
For example, some users may only do basic browsing while others may use their browsers for more intensive work/play. It's quite feasible that one browser may be more efficient with some types of browsing, while the other is more efficient with other types of usage.
Also, different users will configure their browsers differently, and in some cases the hardware they have will also play a role. As an example, some users may have Chrome configured to use hardware acceleration when available (and it's availability will depend on their hardware).
The best way for you to answer this question is to do your own testing with your own hardware and using your browser as you typically would. And it seems from your question that you're already doing this.
Any responses from users (me included) who share their experiences with these browsers are not necessarily going to apply to your usage. And all answers will be equally valid, regardless of how different they may be.