Unlike the Bio Ionic’s handy digital temperature control, the Chi Air uses a small dial on the side of the tool that’s harder to read. The dial’s placement makes it not only more difficult to get an accurate reading, but also more prone to being hit by your hand and switching to a new temperature. That being said, most of our testers didn’t mind this minor inconvenience since they don’t expect to change the tool’s temperature often.
With well over 25,000 reviews, the HSI Professional Ceramic Tourmaline Ionic Flat Iron is one of the best straightening irons you can get, but because of its thin build and rounded plates, you can also use it to curl your hair. It’s got solid ceramic plates to reduce damage, evenly heat hair, and promote shine, and if you’re a traveler, it’s got a dual voltage that can be used anywhere in the world.