Did you hear them at a Celine Dion concert yourself? Maybe they were harsh there, too. You may have different tastes in what you like than Celine's live show producer. It's also possible that with proper EQ and a little compression the GPO strings could sound a lot better.

I normally compare them when I pull up a legato or lush violin ensemble patch with no EQ, and like the EastWest a lot better. Some people even like the Miroslav strings, which are very harsh - but work for some of the "Hollywood Strings" sounds. If GPO floats your boat, that's cool. Different strokes for different folks.