Quick Star is a very good horse, you can see it by its results (500.000$ of profit with its rider Meredith Michaels-Beerbaum) and its descendants that also have good results (Big Star, Quatrin de la Roque, Orient Express, Quick Star 11,...). He was elected "best father of young horses in 2008.
He sure is small (1.59m) this is why breeders recommend to put him on quite tall mares. He brings a lot of qualities such as strength, blood and bravery.
I hope i could answer your questions, don't hesitate to ask me if you need any more details :)