This is cheap way of creatively shooting in the sun (or studio). Ok these do not compare to the Lastolite's, they may be similar but they are not. These are reasonably well made Chinese copies. The downside is that you have to zip the alternate covers over the original frame, a pain sometimes as the zips aren't a perfect fit.
But to be able to carry such a diverse range of diffusers/reflectors in one bag for such a low price is remarkable. The reality is that once expanded the reflected light from say the silver finish is indistinguishable from any other reflected source.
With such a reasonable cost, it is worth every penny to any amateur/pro who otherwise wouldn't carry a set, and as a press man there are times when for instance, you might have to shoot a full length back lit portrait in blazing summer sun, no amount of fill-in is going to help, but a carefully angled reflector........
Also shooting fill flash through a diffuser is also another great effect, far better spread than the small plastic diffuser that comes with pro Nikon and Canon flash. So overall great value, but the build quality is what you pay for, having spent a fortune on Lastolite over the years, and on the odd occasion leaving them behind on a busy job, I would recommend these.