The tricky thing about waterproof materials is that blocking water from one direction inevitably blocks it from the other. Sportful's Fiandre NoRain Pro Bib Tights are the case in point. Compared to the Team and standard version, they block more rain and road spray, but they do so at a slight cost to breathability. That sacrifice is no big deal on base miles, though, where time spent in the saddle is more important than time spent hammering through intervals.

The reasons for the increased thermal protection and the decreased breathability are twofold. As in, they involve two folds of material on the leading panels. That extra layer of material creates a more robust barrier against wind chill and extra negative space to preserve body heat—again, more important for long, low-intensity miles. For quick interval or hill repeat workouts in cool weather, a lighter tight may be more appropriate.