Does different percentage chocolate set differently?
For glazing the best is to use a couverture chocolate which is richer in cocoa butter than the standard chocolat (more than 31% for dark chocolate): https://en.wikipedia.org/wiki/Couverture_chocolate
But generally you can't find it in supermarket and you will need to buy or order in from a specialized shop. And when you check the nutritional informations, a lot of chocolates we find supermarkets will also have a cocoa butter percentage higher than 31%! The problem with these is that they are often the low quality chocolates, and their taste won't be so great and have a negative impact on the final taste of your cake...
So the best way is to try different types, ideally with the same recipe, and see which one works the best! Be patient, it took me forever to find an acceptable one... Also, make sure that your glazing recipe is good!