Titleist's new Pro V1 and Pro V1x balls have a tough act to follow. Consider that their predecessors (released in 2007) combined for 26.2% of balls sold in this country through December 2008. (Source: Golf Datatech).

These new designs are based on Titleist research with thousands of amateurs who play premium "Tour" balls (Titleist and otherwise). Findings indicate that better players want their ball to be longer (okay, so who doesn't?) and to be more scuff resistant.

"Admittedly, we can make incremental distance improvements today, more so than monumental ones," says George Sine, VP, golf ball marketing and strategic planning worldwide. "It's so player-dependent, though. Some may see 3- to 5-yard increases versus the prior ball, others may see 1- to 3- yard gains."

Regardless, both balls have a more durable urethane cover (few golfers will feel a difference between the old and new models). Pro V1 spins more than its successor, for improved mid- and short-iron performance, and flies on a lower driver trajectory. By contrast, Pro V1x spins less than the ball it replaces. The by-product is added distance and more penetrating iron flight for those who tend to impart too much spin. ($46 per dozen; titleist.com)

How they stack up to the previous balls: