I really have no idea of what the Italian or Spanish versions of this film look like. But the Greek one doesn't look that bad and it appears unmistakably at least once a year in the Greek TV, during the anniversaries of the battle of Crete or the German or Italian invasions.
The action is of theatrical rather than cinematographic kind and fails to satisfy the international public, used to the spectacular "realism" of the Hollywood flicks.
Unknown outside the borders, the actors were very well known in Greece at the time (some of them still are today) and for a Greek movie it was not that cheep. Trying to turn it into an international production didn't work that well and it is clearly distinct among Greek war movies for that.
True to the spirit of the time (a military dictatorship was running the country) it tries to glorify the allied struggle against Nazism, underline the usually forgotten Greek factor in the WWII and whisper accusations about the failure of the anyway doomed Greek defense against the German invasion.
I guess the strong point of the Greek cinema was hilarious cheep comedies and human dramas rather than imitations of war epics.