What is the best hair straightener for thick hair?

i have really thick hair, and it use to be long, but i got it cut to shoulder length recently. i want something that i can use when my hair gets long again, as well, without doing a ton of damage. that's what i'm looking for. something that doesn't do a lot of damage. i prefer to let my hair dry naturally, and when i do that, it gets frizzy and wavy. i've heard that 1.5-2" is the best for thick hair. also, the brands i'm currently considering are: hai, babyliss, andis, and chi. are those any good? what's the difference between a pro, elevate, ultra, etc. i have no idea what i'm doing! lol thanks!