Fit: Lightweight and secure fitting upper
Ivan: I always found the upper in my former version a bit too accommodating and especially the width and midfoot hold caused me some issues. Being marketed as a stable long-distance model it was to be expected, but I remember always having to re-lace the shoe during my runs to get a reasonable fit. I am happy to inform you that this has been significantly improved in the Caldera 6 despite an even broader platform. My narrow heel still suffers a bit from a quite broad heel collar but this was easily fixed with a heel lock.
However, the midfoot hold has been significantly improved. Very secure without being too tight helped along by a well-padded semi-gusseted tongue. The toe box is accommodating and leaves just enough space for the feet to swell a bit on those long runs.
The so-called lightweight air mesh of the Caldera 6 is pleasant overall with extra padding around the heel collar. It is not super thin but I have had no issues with breathability during my summer runs. Also, the fairly padded tongue has some nice perforations.
Living in Denmark, trail running rarely gets very technical but I don’t consider that the intended purpose of the Caldera anyway. It is more of a relaxed and stable trail cruiser. However, a few nice trail features have been included. Such as a protecting toe cap, front and back attachment points for gaiters, and a convenient lace keeper.
Alex: The Caldera 6 came to us with a flashy yellow upper that certainly does not go unnoticed. Aesthetics aside, it appears to be a very reliable and sturdy upper, built to last the distance. The toe bumper overlay does not show a single sign of wear on my pair and I can imagine it lasting well over the shoe lifespan. The fit is generous in terms of volume, not necessarily something I enjoy a lot but certainly a key feature for people considering this shoe for long distance events. My biggest struggle in this upper is definitely the tongue. It’s pretty much the first thing the top of your feet “meet” when stepping in a shoe, and here the tongue material is too rough for my liking. It also lacks the required flexibility to wrap the foot nicely. The fit is a true to size but narrow heel will likely find the heel cup a bit too wide. Not a big deal but something to keep in mind when picking the right shoe for a given terrain. My highlight in this upper is the smart lacing system. The eyelets are actually the top of side “wrappers” that envelop the midfoot perfectly in combination to the semi-gusseted tongue.