With that goal in mind the websites listed below are a couple other sites you might find useful.
We’re not affiliated with any of these sites, but anything listed here has received my personal seal of approval

Marketing Experiments is run by a small group of exceptional marketers. The site was originally flagshipped by a brilliant marketing psychologist, Dr. Flint McGlaughlin.
Marketing Experiments, in conjunction with Marketing Sherpa has
- Research and marketing case studies (with actual numbers)
- Insightful videos (copywriting and conversion optimizing)
- Results from A/B split tests (spanning some 20 years)
Swipe-Worthy is a plethora of great swipe files. If you’re looking for inspiration for your next winning control piece, this site is worth checking out. You can search by niche, by type of copy, by control, or by particular copywriter.
The owner of the site, Mike, seems like a good guy (never met him in person, but anyone who creates his kind of website is OK in my book) and he even breaks down and analyzes a few elements in some of the swipes.
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