In general flatter radius fretboards (12") would give you more playability. 9.5 in fret board radiuses are more for vintage feel and vibe. But they tend to "fretout" when you're bending strings. What this means is when you bend a string far enough the string actually stretches and touches the fret that is closer to the bridge and deadens the note or you get fret buzz.

Flatter the better for playability. As with most things with guitar, there are functional differences but the main thing is individual preference.