Fins are a difficult subject to cover with any degree of objectivity. Each new model is hyped as ''the best,'' and this claim is usually backed by obscure hydrodynamic theory, performance data extracted from a robotic swimming simulator or scores from a timed ''swim off.'' But in my experience, the only way to evaluate a fin's overall performance is to get out of the lab and into the water.  And after 25 years of diving, I still haven't found a fin that is ''the best'' for all divers and all conditions. For example, a fin that provides efficient straight-line propulsion for a diver of average strength may not develop enough thrust to move a diver wearing double tanks or the versatility needed to hover and pivot while taking photos. Recently I was asked to provide exactly this type of real-world evaluation of Mares' new Volo fin. To do so, I loaded a gear bag with a half-dozen styles of fins and headed to Palm Beach for a week of drift diving in the area's typically brisk currents. Up front, I will confess to a pro-Mares bias. For more than a decade, the company's Plana Avanti was my fin of choice for wreck and cave diving. A few years ago, I switched to the Quatro - open heel for cave and cold water, full-foot for the tropics. This bias actually worked against the Volo on my first dive, as it had an unfamiliar feel and didn't seem to develop as much kicking power as the Quatro. On the second dive, I carried both models and switched repeatedly underwater. The unfamiliar feeling, I realized, was the result of the Volo's unique pivoting blade design, which transfers the flex point of the blade from the toe area to the center of the fin. Mares engineers explain that this design allows the blade to maintain an optimum angle of attack throughout the kick cycle. I can't speak for the physics, but I can attest to the comfort, and I also noticed that the Volo seemed to bring the large muscles of my thigh into play. The absence of pressure on my toes and calf muscles fooled me into thinking the Volos weren't moving as much water as a stiff, conventional fin might. But in reality, I was simply spreading the load over a wider area of my lower body. My next 10 dives were spent making head-to-head comparison swims against a variety of flat, vented and split-blade fins - all while towing a float marker on a 100-foot line and navigating in a stiff current. My findings could be summed up as follows:
  • In straight-line swims, the Volo provides a high degree of swimming efficiency, perhaps not as great as some of the best split fins, but certainly more than the majority of single-blade fins.
  • When performing sculls, frog kicks and other techniques used to maneuver or hold position, the Volo compares favorably with the best conventional fins and outperforms most split-blade fins.
  • The Volo provides a high degree of comfort, thanks to its ability to bring the entire leg into play and minimize toe flex.
  • Stiff fixed-blade fins provide an unmatched ability to move heavy loads, but the Volo can produce almost as much thrust with far more comfort.
    • I probably won't be trading my specialty free-diving blades for Volos, nor will I be wearing them on cave dives. But for everything in between, these latest-generation fins are a prime choice. They offer an unprecedented combination of swimming efficiency, comfort, maneuverability and power. SummaryThe combination of Mare's patented Channel Thrust and pivoting blade technologies allows the Volo to transfer stress away from the toes and creates an extremely efficient fin with a balanced blend of power, comfort and maneuverability. Suggested retail is $199.