The Valkyrie is a relatively understable distance driver. With its speed of 9 it sits on the line between a fairway and a distance driver, so it needs to be thrown with good form to fly properly.
That also makes it a really good transition disc for beginners who have started to overturn their slower understable fairway drivers and want a disc that still glides far without turning into rollers half the time it is thrown. For experienced players it is a good disc for turnovers and rollers.