New Balance's Vazee line of running shoes has always been aimed at neutral runners like me, whose feet arch normally.

The Vazee Pace ($189) that I have been testing for the past three months is one of the most comfortable running shoes I have worn.

These shoes still feel responsive, despite the high mileage I have put on them. But if you are flat-footed, they are not for you.

You should instead get the new Vazee Prism, which is designed for flat-footed runners, who need extra stability.

A dual-density medial post is integrated with the rear foot area and extends into the arch zone to curb overpronation, which can be an issue for flat-footed runners.

To further enhance stability, a bootie construction wraps the arch.

The Prism has a slightly higher heel drop - the difference between the height of the heel and the midfoot - of 8mm. The heel drop is 6mm in the Pace.

Flat-footed runners generally find a higher heel drop - 10mm to 12mm - more comfortable.

Both shoes have New Balance's proprietary Revile midsole, which uses an "intelligent geometries" construction to improve response. Its rubber outsole has a pod-like design in the forefoot area to aid transition during foot strikes.

But, frankly, I could not tell the difference between the Pace and the Prism. That extra 2mm heel drop did not feel uncomfortable.

To me, they performed about the same. Both felt as responsive with each lift-off and as cushiony when my feet hit the ground.

Neither needs any breaking in. I ran in the Prism without socks. It fit like a glove, yet offered enough toe room when I pushed off.

The only downer is that the Prism, like the Pace, is not well ventilated. Both can become rather warm after you hit 5km or so.

Trevor Tan

•Verdict: Those after a pair of responsive running shoes will find the New Balance Vazee Prism a good fit.