None really, if it where stolen or got lost i would not buy another.

Velcro strips
Have to pump it up with air, it could leak at some stage
poor diffusion

Intitially i felt dissappointed at first on opening the product, the front window is less diffused than the picture on photoflex website, the velcro attachment is a total disaster if you have a flash gun that adjusts for wide normal and tele lenses because the side velcro strips cannot be attached properly, a tight elastic set up would have worked better.
If the front aperture window was the same or similar material to a white umbrella i think better diffusion would occur,It certainally diffuses the light better that a straight flash, but i was hoping for more of a soft box effect but not so, I am thinking of modifying the front somehow to create more of a soft box.
However it is better than any self made diffuser i have created and it does spread the light with only one stop loss at 3 meters.

Similar Products Used:

Home made diffusers that worked better but more difficult to mount