SPS :
Jet be is a mix of 60% kerosene and 40 % naptha(if my memory serves me correctly), it burns hotter and is definietly easier to get a light-off in cold temperatures. The engines in the question are not theoretical but certified civilian engines.
I think with a 1000 litres of Jet A an A/c would go farther than with Jet B. That being said I've had pilots argue that you get the same range because Jet B gives the same performance as Jet A with reduced fuel burn allowing one to go the same distance on 1770 lbs of Jet B as 1850 lbs of Jet A1.
Never been able to find the proof in text, to dispell or confirm the difference.
IHL