New Balance Fresh Foam X Hierro v9 Review: Fun, Looks Cool, Could Lose Some Weight

The New Balance Fresh Foam X Hierro v9 is a trail shoe that feels like a big step forward in blending comfort, durability, and modern design. The Hierro line has always been known as a “cushioned cruiser” for the trails, and with version 9, it feels sleeker and more agile without losing that plush underfoot feel. What struck me most was how well it balanced being protective enough for rugged terrain while still feeling smooth and fun to run in. Whether I was tackling rocky paths, rolling singletrack, or even a bit of road to get to the trailhead, the Hierro v9 felt like it could handle it all.

Technical Specs

Weight: ~314 g (men’s US 9) / ~11.1 oz
Stack Height: 34 mm heel / 26 mm forefoot
Drop: 8 mm
Midsole Foam: Fresh Foam X (EVA-based supercritical blend)
Upper: Engineered mesh with TPU overlays and toe protection
Outsole: Vibram® Megagrip with multi-directional 4.5 mm lugs
Fit: True to size, medium fit with roomy toe box

Upper

The upper of the Hierro v9 feels rugged but comfortable. The engineered mesh is reinforced with TPU overlays that add durability and protection without making the shoe feel overly stiff. I liked the built-in toe bumper—it gave me extra peace of mind on rocky trails where stubbed toes can happen quickly. The tongue and heel collar are padded just enough to create a plush step-in feel, and the fit across the midfoot felt secure without being tight. The toe box has that slightly roomier New Balance feel, which made longer efforts much more comfortable. For me, it struck a nice balance of trail-ready toughness and all-day comfort.

Midsole

Fresh Foam X is the star here, and it gives the shoe a smooth, cushioned ride. At 34 mm in the heel and 26 mm in the forefoot, the stack height provides plenty of protection for long runs, but the foam feels more responsive and less mushy than earlier versions. The 8 mm drop worked well for me on climbs and descents, keeping my stride natural but supportive. I noticed that even on long days, the cushioning stayed consistent, helping to reduce fatigue. While it doesn’t have the bounce of some plated or PEBA-based shoes, it offers a reliable comfort that makes it easy to keep piling on miles.

Outsole

The outsole uses Vibram Megagrip, and it’s as good as advertised. The 4.5 mm lugs are aggressive enough to bite into dirt, gravel, and loose terrain, but not so deep that the shoe feels clunky on firmer ground. On wet rocks, I felt secure, and on dry, dusty singletrack, the grip held up well. I even tested it on a few road miles, and while you can feel the lugs, it didn’t feel awkward or overly harsh. After several outings, the outsole showed minimal wear, so durability will be a strong point for the v9.

Performance on the Trail

Out on the trail, the Hierro v9 felt like a versatile workhorse. On easier, flowing trails, it cruised smoothly, and on more technical sections, the stable platform and grippy outsole gave me confidence. It’s not the lightest trail shoe out there, so I wouldn’t pick it for all-out racing, but for daily training, long runs, or ultra-distance efforts, it really shines. I found it especially good for those mixed-surface runs where you might encounter everything from pavement to rocky climbs—it just feels adaptable. The cushioning kept my legs fresh, and I never felt beat up even after a couple of hours of running. They are a bit heavy compared to others in their class so definitely an area NB should look at and for you to consider.

Conclusion

The New Balance Fresh Foam X Hierro v9 is a trail shoe that delivers comfort, durability, and versatility in a single package. With its protective upper, cushioned midsole, and Vibram outsole, it’s built to handle everything from technical trails to light road miles. It’s not the fastest or the lightest shoe, but it’s incredibly reliable, and for me, that’s what makes it such a solid option. If you want a shoe that can handle long days on the trails while keeping your feet comfortable and secure, the Hierro v9 is an easy recommendation.

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