“It carries a guide number of 48, which means it can cast usable light from a maximum of 48 meters”
That’s a bit of an oversimplification, don’t you think? The correct definition would be something like this. “At full power, it can provide proper illumination from a distance of 48 metres when using an f/1 lens and a sensitivity setting of ISO 100/21°, as long as you shoot without a light modifier.”
Otherwise a fine review (though I do believe Biowizard has it right and you ought to substitute Watt seconds for Watts). What I do miss are the t0.1 and t0.5 figures, even if I realise they do not matter much when using a 5D Mark III with its measly 1/200s sync speed. Some of us use cameras that sync at much higher speeds and it does matter if the t0.1 time at full power is 1/200s or something closer to 1/500s.
Started out doing photography at the age of 6 using an uncle's old 1940 kodak brownie box camera. At 15 years of age, I decided to buy my very own 1975 Praktica SLR camera. I now shoot with a Nikon D850. I do unpaid TFP and commercial paid work.