Nothing major here, but since the set features several Hall-Of-Famers and highly-collected players, here’s a look at the two varieties that can be found in the All-Star subset of Score’s inaugural NHL issue:
A. LIGHT BLUE line on back, over text.
B. DARK BLUE line on back, over text.
Junk Wax Gems 
I checked both the American and the Canadian version of this product and it seems that the variation is only in the American version.
I have only found it in the American version as well.