I'm going to try year-round bike commuting. My commute is 3.2 miles in Central Wisconsin. Part of the reason for cycle-commuting is to stretch the budget. However, I'm learning that it costs some just to get prepared.

I'm looking for a shell layer that would work double duty as wind protection and rain. I'm leaning towards getting a Frog Togg suit. But I don't think they have winter cycling in mind when they make them. Frog Toggs are excellent in rain. They seem to offer fair wind protection. And they fit my budget.

However:

Do they get brittle when the temps drop?
Will they hold up to daily bicycling? Abrasion points at legs.

Or is there something else that you guys highly recommend?

My commute is short so I'm planning on wearing regular cloths under my cycling outerwear (I'm hope to avoid spending an hour getting dressed/undressed before and after a 20 minute commute). So I'm interested mainly in over-alls not necessarily tights.

I have a pair of Novara fleece lined tights that are very water resistant. They are good down to about freezing. If it gets much colder than that, I can add another pair of microfleece tights under those without getting too bulky to pedal. They are designed for biking, and seem to handle the wear of pedaling just fine.

Upper body is less of a hassle, and just about any bike specific (because they have the longer back) rain jacket will work. Just layer underneath as much as you need, so don't buy one that's too tight.
My Novara upper is good for light to moderate rain. It's warm, windproof, and breathes fairly well. But if it really gets cold, or starts raining hard, I'll put the rain jacket over it. I always wear a base layer underneath the Novara, and just vary the layers depending on the temps. I prefer to layer, since there can be a significant difference between morning commute temps and the afternoon commute.

I live in WI and commuted since the 70s. No rain: LL bean wind pants, not sure if they make them yet but they zip from waist to ankle this is important part, because its easier to change at work. Rain: shower pass rain pants or marmot pants (don't know the name but its lightwt and water resistant and windproof) I have both. Cold then I might switch to marmot that has a light fleece lining. for the top, I go with anoraks that zip up to the chin or above, i have several different types, but LL bean works great with no rain but when it rains then I go with whatever else I have. In the winter its always layered with polartec. I would say I have about 3-4 different types of pants for various temps and weather and probably about 4-5 different coats and layers for same purpose. don't even go in to the gloves, I would hate to say how many of those I have. I tend to get cold hands and feet very easy. I would easily say my Giant VT2 has 25K miles on it most of it commuting and try to go all winter. I always wore my work clothes under my bike stuff, its much simplier and faster to change except in the winter when its very cold then it takes forever to get dressed and undressed