I placed this Review after picking one up at BH photo.
Like others said, this should be included with every head and only $39 if not less. Haven't test it on a beauty dish as other have ... only on medium and large Chimera boxes and Profoto 1x4 strips. All of us old film shooters were shocked the B1 and D1 flat glass panel was the ' standard ' configuration straight out of the box. I finally got around to buying a dome and testing outputs with and without. There is still no comparison when using this over a pure bare bulb head such Profoto's Pro B head or other manufactures like Speedotron. With my Profoto B1, I measured a 1-1/3 of a stop difference between the center and far outer corners of their 1x4 strip ( and yes ... I had the baffle in there too ) without this frosted dome. With the dome it's a little better but still around 8/10's of a stop hotter in the center.
On my Speedotron and Pro B heads, I measured it around 4/10's of a stop ( a full stop difference better) !!!
You can see how harsh the center hot spot is with the naked eye in the front panel with just the modeling light without the dome and a little better with. This dome I would say is 1/2 as effective as using a pure bare bulb head. I know some will say the B1 modeling light is back behind the tube so using the modeling light is not an actually representation of the tubes true spread across the panel. Just test it yourself and you'll sell what I mean. The distance between the speedring and outer panel on my large Chimera box is 30 inches so with the test image I attached here, I placed the D1's tip of the dome 30 inches from the wall.
I'm thinking about putting a piece of foil inside at the tip with tiny holes to help further reduce the hotspot. Real pros understand what I'm talking about here. The inside walls of the boxes and strips need more light before hitting the front panel and baffle. Profoto I'm sure doesn't want more loss out of the dome so this is what they came up with. A bare bulb would have nuked my floor in the sample test shot. What I see is a softer transition but it's still pretty hot in the middle.