For those familiar with my work, for portrait, lifestyle, and fitness, I've been using either the 36" x 48" softbox or 12" x 50" stripbank as my Key Light. I would also put a 40° egg crate grid on the softbox or stripbank. About a month ago I did a shoot with the Westcott 7' Diffusion Parabolic Umbrella. Yes it is a huge umbrella. What I like about the 7' Parabolic Umbrella is how the light wraps around the subject and you could take a full body shot without having to set the light further. What I didn't like about it was, it's difficult to control and shape the light. If you are looking for a large soft source of light you can't beat the 7' Parabolic Umbrella. For around $100 you get a large soft source of light. If you do decide to get the 7' Parabolic Umbrella, I recommend getting some black fabric, so you can put it over the umbrella to shape the light.
Next came the Westcott 54" x 72" softbox. I've heard about it several times but have never seen one. As I was preparing for a test shoot with my good friend, Maynard, who also happens to be a great photographer, I needed additional c-stands and sandbags -- safety first. I rent most of my equipment from Keeble & Shuchat Photographyrental department. They have a well-stocked rental department. While I was there, I noticed they have a 54" x 72" softbox. Took them awhile to find it. Apparently it's been a long time since anyone rented it.
Here is my setup.
Key Light - 54" x 72" Westcott softbox with 2 36" x 48" 40° egg crate grids (I didn't have a 54" x 72" egg crate grid).
Key light set to f/5.6.
If you are interested to know more about grids check out this video.
Hair/Rim Light - 12" x 36" Westcott stripbank with 40° egg crate grid.