Maintenance controls the speed and the roll.
A good poa can be the superior turf to putt on but for most of the year it wants to die.... so bentgrass is a better alternative for consistent conditions. Generally bentgrass lays over so can be more grainy whereas poa usually "stands up" better. Saying that poa adapts quickly so it can have many different characteristics (even on one green) so not all are upright growing.
Topdressing, thatch management, mowing height and moisture are the biggest contributors to smoothness, trueness and speed no matter the grass type.