Just wondering if anyone has used these light-weight wheel nuts off e-bay:

RED LIGHT WEIGHT WHEEL NUTS (SUBARU IMPREZA, etc) on eBay, also, Nuts, Car Wheels, Tyres Trims, Cars, Parts Vehicles (end time 03-May-08 21:24:21 BST)

I got a set for my own car but have heard various horror stories that they can come loose and 'fly off' and you can strip the threads when tightening them etc....Has anyone any experience of these at all or could shed any light on what they are like to use as i wouldnt risk them if they aren't safe??....If this is the case i will just get a new set of standard wheel nuts

Cheers

Kevin