I've only had a chi so my answer is probably biased, but I've had mine for over 2 years now and it still works great.(: Considering the times I've stepped on it...dropped it...left it on all day on accident a few times...I'm a bad straightener owner. It heats up really fast too which is a plus.
I'd buy the Chi. I have one with the ceramic plates and purchased it 3 years ago. It warms up very quickly, makes my hair very silky and works well on my long hair. My hair is in the middle of my back.
i know this isn't one of the choices but get a paul mitchell those things are amazing! and yes I have had a chi and it totally fried my hair like litterally it was totally burnt and had to cut my hair waay short because there are no heat changing options on the chi. paul mitchell all the way!
My iron is called Fahrenheit It is simply amazing, my hairdresser recommended it to me. I got mine at either TJ Maxx or Marshalls for 30 bucks. I used to have Solia and Sedu and this was better than both of them.