At the risk of sounding like a broken record, I'll mention Dawson Precision. They make very good target sights for the PPQ with the advantage they can customize the sights to your preferred sight picture by varying the widths, heights and materials. For target shooting with the PQQ it is a good way to go.
I second Oldfarts recommendation on the red dot though. It's a definite and addictive advantage for target shooting. That advantage becomes more and more pronounced as our eyes...ahem...mature.