I never liked CCC for some reason, not sure if it was the UI or what. Been rocking Keepa for many years without any trouble. I set price notifications for items that I can wait for, but usually check price history for everything else.
I'm actually glad that the Amazon wishlist also tells you that an item is now priced lower than when it was added to the wishlist. It makes it a little easier to identify price drops.
I love Keepa, and the Firefox addon. However, they seemed to nerf their wishlist features (auto sync problems, 10 items max, etc). Noticed after missing deals, due to not receiving alerts of price drops. Still very useful, but CCC now has more reliable auto tracking lists (just add to wishlist, it will auto sync and email any drops).
I’ll advocate for the CCC Firefox extension, but email alerts are the big ticket item. If I know there’s something I want to buy, I’ll set myself a price that I think is reasonable and just wait until I receive an email saying it’s hit that range.