Dynafit ONE PX TF 30.0

Christmas in November! When ZZero PX boots failed under warranty, Dynafit/Salewa sent a pair of the new Dynafit ONE PX as a replacement. Stoked.

Finish and mechanical quality is excellent. Boots are comfy and solid around the house. Palpably stiffer than the ZZero PX, but the walk mode is superior to the TLT4. I anticipate that these boots will ski well.

The one-buckle cuff closure/lock is awesome. I hope I can avoid trashing the buckle on rock when scrambling. With smaller ONEs I’d examined in a shop, I’d been worried that the lower buckles would be exposed to rock damage, especially the instep buckle. On the 30.0/30.5 shell, they’re placed pretty high; not perfect, but better.

The clean inner cuff/shell design is really nice. Nothing to catch on or be destroyed by ski edges, just smooth burly plastic.

The now-requisite Dawson side-release test was qualitatively consistent with my TLT4s. The Quick-Step fittings worked great for carpet-surfing click-ins.

BD Neve crampons go on easily. Orange color even matches the boots.

Soles are thicker than the ZZero, for which I’m thankful. A few April/May climbs and traverses with the ZZero had worn the heel and toe rubber, exposing the heelpiece, which cracked the heelpiece screw internally, hence the warranty.

Weight / Mass: Left boot:  1791 g, Right boot: 1790 g (the scale requires a 0.2% correction). Assuming a normal distribution, this yields 1790.5±1.3 g. If this consistency actually reflects the manufacturing variation, it’d be impressive.  3581 g/pair, or 7.89 pounds. BSL is marked as 334 mm.

Liner weights (372.1 g, 372.0 g) agree to a tenth of a gram, or 0.03%, despite having been made for different feet. Excellent work, Dynafit.

Incidentally, since Pebax has density of 1 g/cc, the boots are actually 2.15 g heavier than I quote (and the wearer would feel at sea level). They’re floating a little bit in the atmosphere,  as a buoyancy correction would show. More practically, they’d feel like they weigh 1.43 g more at the summit of Mt. Everest.

Updated this post with reviews:

Edit 12/3/2012: Skied them yesterday.

Pros: Tour mode is great, Significantly stiffer than the ZZero4 PX; stiffest boot I’ve used in years. Like them. One-buckle cuff/latch is sublime.

Con: Unmolded liners squashed my feet, but that’s what they’re supposed to do. Thermomolding should clean that right up.

Edit 12/8/2012: Skied again today.

These boots are great. Still haven’t molded them, but they hurt less this time around. Cuff movement is sublime. Found that the the power strap significantly alters the stiffness. For smoother flex, just don’t tighten the velcro.  Great boots.

Edit 12/10/2012: Skied POW! yesterday. Stevens Pass won the biggest convergence zone lottery anyone can remember.

Still great. Less time in transitions and more efficient stride. Too busy skiing pow to mold the boots, so they hurt a bit. The stiffness of the boots lets me drive my El Hombres in a way the ZZero4 PX never could. I’m sure a lot of it was the excellent snow, but I’ve never felt more confident ripping in pow.

Edit 2/8/2013: Still very happy with these boots. Still haven’t molded them, but they’ve broken in very comfortably. Have taken them on some alpine rambles now. They ski super well. Cramponing with them works well enough, though the stiffer upper cuff makes french technique less attractive. Scrambling verglas-covered rock made me fearful of destroying the upper cuff buckle. They took a few firm insults with panache – paint hardly chipped. That said, the protruding buckle is a problem, one that’s tricky to fix.

Edit 12/9/2013: With a full year on them, I’m still very happy with these boots. The only sign of wear is that the power-strap velcro is starting to delaminate right at the fuzz/hook transition. I’m not a connoisseur of ski boots, but these are the best boots I’ve owned. Soles are durable/wearing well, though I haven’t hiked on them as much as I’d have liked. Good boots.