If your feet suffer on Winter rides then it's worth getting an insulated boot to keep the chill off your toes. Shimano's RW80 is certainly one to look at, with a full Gore-Tex Duratherm liner it will keep the rain and the cold out.
The RW80s are solidly constructed with a full PU-coated leather upper which is topped off with a Neoprene sleeve and Velcro strap. This helps to keep your ankles warm but more importantly stops water from getting in the top on wet rides. The rest of the boot is completely waterproof thanks to a Gore-Tex liner that extends right across the tongue and under the insole.
The polyamide sole is plenty stiff for the road, but since this is specifically a Winter shoe it's disappointing that there isn't more tread on the heel. Three Velcro straps keep the whole thing nice and tight and there's discreet but well-placed reflective on the sides and back of the RW80.
Given the size of the shoe they're not massively heavy (claimed 750g for size 40, our 47s were 925g), though obviously they weigh much more than the equivalent Summer shoes in the range. That's not a big concern though when the main issue is whether they'll keep you warm and dry. And that they do very well. The Gore-Tex membrane keeps the wind out and the insulating layer and full leather outer mean that it's plenty warm inside. Even on really cold mornings they're fine without an overshoe. The Neoprene sleeve does a great job of stopping water ingress, so long as your socks don't poke out of the top.
The fit is nice and snug, I found the toe box a bit narrow to begin with but my feet are wide and the toe box is starting to stretch a bit now too, all in all they're pretty comfy and I didn't suffer from numb feet or hot spots. On really cold days they're not so big that you can't add the extra warmth of a pair of (big) overshoes, with that setup there shouldn't be any weather to stop you.
Should you get some? Well, if you really suffer from cold feet out on the bike then you should certainly check them out for yourself. They're well made and should last a good few Winters, so although the initial price is high these boots, like their MTB equivalents the MT90, should prove to be good value in the long term.