Hi Mollusc,
To give a satisfactory to the question raised, one
should consider where the tanks mounting different types of guns were deployed facing each other.
In
the wide open spaces, where Tigers were able to fire at enemy tanks, outside the latter's killing range, kudos must go the the 88 mm, however, when deployed elsewhere they belong to others. In the Pacific and Far East theatres to the US 75 mm, in North Africa and Italy to the British 6 pdr.
In the hills of
Tunisia and Italy the advantage, over both Tigers and Panthers, belonged to the Mark III and IV
Churchills with their higher rates of fire and the ability to faster lay on their targets. The following is of interest: http://www.northirishhorse.org/nih/Documents/25TB-TechSummary.html
Cheers, Gerry