The effect is mediocre bad, other diffusers (also plastic yogurt cups) can better.
My Recommendation:
- Either a bit smaller with the original Kuststoff diffusers of the manufacturer (or exact copies :)), with the disadvantage that you need for each flash diffuser (which may be all no matter who only a flash), or
- A bit larger: There is little or Octaboxen softbox for the flashes (as 15x15 up to 25x25 cm, for example, the Lastolite Ezybox Speedlight (ok, about 50) or the E-20 Jinbei Diffuser Octabox (about 16 !!!) . This will definitely have a much better !!! diffuser effect and can be used universally (flash model dependent). Disadvantage: Bigger (is that a disadvantage acts but also professional :)?)
If one considers how positive the flash is changed, you can spend a few euros more small already, just rather not for this model here. :)