I just picked up the Westcott Rapid Box 26" Octa. When I first unboxed it I was very surprised at how high quality and solid this little thing is. I'm still amazed by it. Usually inexpensive umbrellas are super flimsy and cheap feeling. Not this sucker.
Here it is on Amazon: Westcott Rapid Box 26" Octa Softbox
There is also a 20" model that is cheaper.
So far it seems to work very well as a 26" octa soft box with my canon 580 EX II speedlight and a sock covering it. The lighting is very even throughout and I don't feel like there is any noticeable hot spots with the sock cover.
I haven't tried it without the sock. I imagine it would give a large but very hard light source. Like a mini Parabolic.
I also purchased the Beauty Dish attachment. It seems to work pretty good as long as you can find the sweet spot. One thing I instantly noticed is that if you point the light at too much of an angle trying to feather your subject with it, you'll get in direct view of the speedlight that is not blocked by the dish. This creates a lot of spill. I'm thinking I might have to move my speed light further back to help with this, but ultimately a grid would be really nice for trying to use this as a beauty dish in tight spaces where you don't want raw speedlight light going everywhere.
The beauty dish with the diffuser sock is great though. Very even light soft light.
I'll have more samples and experiences as I go. This page like all my review pages will be constantly updated with my experiences as well as the products durability as the years go on.
If there are any tests you want to see me do, leave it in the comment below.