From what I've heard, GHDs are made in a different country to what they used to be and the quality isn't as good. The Cloud 9 is made / designed by the person / company who used to make GHDs. I've had my GHD for 9 years and it hasn't skipped a beat (touch wood) but I wouldn't buy a current model. I'd buy a cloud 9, or MUK which my hairdresser uses.
The thing that makes my thick, curly, frizzy hair very straight for days is a brush / tool like this. After straightening my hair using this (in conjunction with my straightener), I can tie it up, have a hot shower, let it out and not need to run the straightener through it again! My hairdresser explained it holds your hair straight so the straightener doesn't have to worry about smoothing your hair and fighting against curls so it does a better job.