Great product. Second one I have purchased.
If you buy a modifier and it's your only modifier this is the one to get you will get other modifiers and they should all be Strobepro
The grid fits the Rapid Pro Softbox perfectly. It focuses the light exactly how it should. I would definitely recommend this to friends and will be picking up a second one in the near future.
After my first usage: they're great to set up and inexpensive. The outer diffusion panel should be about a centimetre longer as it's a bit tricky to get it velcroed perfectly all around.
I bought a second 12x55" softbox and grid. I am very happy with the quality of the both products.