Awhile back I bought a 48" octabox off e-bay and I finally got a chance to experiment with it. Here are my initial impressions.
EzyBox which shoots the light straight out the front but through two layers of diffusion. The fit, finish, and materials are all of very reasonable quality. It looks professional and I don't have any worries that it's going to fall apart prematurely. In terms of usability, the umbrella design makes it really fast and easy to set up, which is a hard requirement fo me. The octabox included a grid that velcros onto the front rim of the softbox to contain light spill. My initial impression is that the grid is pretty much a necessity for a bigass box in my tinyass studio. The grid works exactly as advertised and the spill that did occur onto my backdrop had a really nice gradient that added to the mood of the photo. One thing that I didn't get a chance to experiment with yet is feathering, but I expect that the possibilities will be terrific on that front with the octabox design and the grid.
As expected a 48" box is more of a workout for a single speedlight than my smaller softboxes, but I still had several stops of power to spare as I was shooting at ISO 100 and f/8 aperture. But I think I will pick up a double or triple coldshoe bracket so I can load it up with additional speedlights when necessary.
On balance I'm really happy with this softbox, especially in terms of its performance as a lighting modifier. It's a no-brainer for the $65 I paid for it.