Heat recycling is good concept to be aware of. So good, that even this product may benefit some people. However note that the positive reviews are in the vein of, "better than nothing." Here are my personal experiences and opinions. For me it was worse than nothing, and a paper cup and scarf are superior. You can do better 2/11, for less money.
1. The fit of the plastic snout is uncomfortable and loose. Other companies mastered a comfortable hugging fit over and around the average nose, a long time ago, for dust masks, goggles, etc. Instead of improving its design, this product now includes one tacky add-on strip of foam, and more replacement strips are happily offered for sale. For me, this inelegant add-on was fussy, unhandy, flimzy, and merely shifted the fit problem.
As the product is pictured worn on the manufacturer's website, the tension which holds the mask binds mostly on the bridge of my nose. Alternatively this mask could be worn higher on the face, but then it would cover the eyes. Or cupped only around the mouth and chin, but there are better designed products if that's all you want.
Any fogging of glasses is in fact the fault of this design.
2. The snout is just a plastic cup. It has no insulation on the outside, and no heat recycling material on the inside. It would be more efficient to breathe into a cupped hand. Note the other reviewer's comment on one of the Talus products, about lots of condensation inside. Lack of insulation aggravates this.
Instead just take any reusable low-profile dust mask/ respirator. You are already better off comfort wise. If it has removable cartridge filter(s), try using it without the filters, or with. 1/11, Amazon sells a good one-cartridge mask. A dust mask provides the same mere air pocket, more comfortably and snugly.
But if you wish to tinker a bit, then also you can combine that with a favorite balaclava or scarf. You could add a bit of thin exterior insulation, such as Thinsulate or stock neoprene. That reduces the inside condensation. You can also improve the heat recycling, the whole point, by adding some copper. Mesh internal to the mask, or mesh or wool adapted inside a cartridge filter which fits the mask, sensibly and simply. However adding it outside increases the problem with condensation freezing the venting. I too was hoping for a good ready-made solution, but for me this product is not it.