For the price you aren't going to do much better than this. This is a well machined little kit. The lenses appears to be glass and aluminium construction. The fisheye is gave us some hilarious pics and is nice and sharp as is the wide angle although there is no distortion correction and some vignetting (for this price you shouldn't expect it either). The macro gets you very close - the macro is part of the wide lens, you need to unscrew the front part of the wide lens and leave the rear part attached to the clip.
Tip: Make sure your iphone lens is clean and attach the clip before screwing on a lens. This way you can position the iphone lens dead centre of the clip. This will ensure that you get the best optical performance from the lens and reduce vignetting.