This is Roure,
I have an experience of using natural human hair wig. Before three years, i have worried about huge hair loss problem due to jaundice. Then, i asked one of my best friends to give suggestions for me. She recommend me to try some natural human hair wigs while going for outing.I bought one lengthy and shining human hair wig from the leading human hair manufacture " Priyankaa Hair Traders". I started to use it while going for outing and attending functions. The quality of the human hair is very good. So, better you can try it!
I've had both clip-ins and sew-ins. The clip-ins I wore religiously for years when my hair was straight. The sew-ins I only had for a few days, because I got them for a special occasion (my graduation ball). I would've kept them in, but I wanted to start wearing my hair curly and they were straight, so that wouldn't have worked.
I've always thought they were awesome though. You just have to make sure, if you're getting sew-ins that you go to a hairdresser you know well and make sure they put enough in, so it looks natural and you don't get those thin ends that make it obvious you're wearing extensions.
I'd also imagine extensions with curly hair would be a bit of a debacle, as you'd have to match your curl pattern.