If you had to choose a single light shaping tool, you might do well to pick the Impact 7' Parabolic Umbrella (Translucent White).
First of all it's a really huge, broad light source that wraps light around your subject yielding clean highlights and rich open shadows. But due to the special shape of the umbrella there's a unique mix of soft enveloping light with the kind of crisp detail you only get from reflectors. This umbrella has a unique design structurally as well. The shaft is reinforced for strength and instead of bendable metal, the 16 inner ribs are made of durable fiberglass.
The white translucent version of this umbrella yields the softest light. Used in standard bounce mode, some of the light escapes through the material, slightly raising the ambient light level and lowering contrast while most of it is directed towards your subject. If you want a harder light, turn the umbrella around and aim the convex side at your subject and punch your light source through it. In both modes you can vary the light quality and output by changing the light-to-umbrella distance along the shaft.
You can also use this umbrella as a scrim over your subject to diffuse harsh light sources like the sun in situations like fashion catalog work outdoors or at the beach. Any way you use it, with the Impact 7' Parabolic Umbrella less is definitely more.
7' Parabolic Umbrella (White Diffusion)
Carrying Case with Strap
1 Year Manufacturer's Warranty