If you ride in cold and wet conditions, you'll want a pair of Hydro GTX winter road shoes for those long wintertime rides. An insulated, fully waterproof Gore-Tex upper keeps your feet warm. The Hydro GTX shoes allow you to have fun riding even in challenging conditions. SIDI's Hydro GTX is one of the best-kept secrets among early-season speed demons.
Diablo GTX mountain shoes and Hydro GTX road shoes employ a four-layer upper for optimal durability, weatherproofing and winter comfort. They feature, from the outside in: A tough exterior of Lorica® panels and breathable heavy-duty nylon inserts. The next layer is a seamless inner Gore-Tex® bootie for waterproof, breathable comfort. There is a third Light insulating layer and finally a soft inner liner.
The gusseted upper fits snugly around the ankle, creating a waterproof barrier where ordinary shoes would allow water to enter the shoe around the tongue. For optimal comfort and performance the wide neoprene-and-Velcro strap must be snug around the ankle, with tights or rain pants tucked around the outside of the boot.
I own both Hydro (MTB) and Diablo (Road) versions of these shoes and have used them for two years in Minnesota Winters. Since the shoes are identical except for their soles any comments apply to both. I normally wear a 43 Summer Sidi shoe and even though these Winter models are supposedly cut larger I went with a 44. The extra toe room is nice but is hampered by the fact that they are too narrow to fit all the socks I would like to wear. I wish they had a Mega version which was wider. I tried replacing the fairly thin stock insoles with a thicker Winter one and had to remove them as the additional thickness caused the shoes to be too tight. I normally wear one/two liner socks with a thick wool sock inside the shoe. This is fine to the upper 30's. When it gets colder I wear Shoe Covers as well. You need a screechy type of cover because the top of the shoe around the ankle is wide. I can ride a couple of hours in low 20's (with a good wind) without any problems.
Pros: Quality Construction, Fairly Warm-Windproof
Cons: No Mega Version
Two winters. Sole is stiff enough but rest of shoe flexes too much. I have wide feet and this shoe is wider than my feet. Uncomfortable for flat feet. Wool sock takes some of the stress away, but guaranteed to come home with sore feet after an hour easy ride. Not sure of its water resistance but it has Gore-Tex material. Shoe will not keep feet warm below 15F (32F+20mph+10mph winds). Shoe cover a must, heel wrap around area exposed to outside air. Shoe will not completely protect your ankles from air. The thicker the sock the more chances for shoe to wrap around heel area. If you are slim you might end up wraping velcro past its mating point therefore enlongating neoprene tongue and eventually ruining your shoe. The ticker the sock the better, I used hiking socks.