Hi, I cycle all year on my cytronex with standard schwalbe marathons. They are OK if you keep your eyes peeled for likely bad road conditions. I haven't come off in snow or ice yet - so far its always been in good conditions and usually when I haven't paid attention to road hazards! Sheffield is not renowned for gritting the roads so I do occasionally have to cycle on very snowy roads to the nearest bus route which they do grit. Even last winter I only dipped out and took the car one day when the weather forecast was atrocious (and wrong - I would not have had any problems as it turned out). The only bike problems were the grit shredding the brake blocks and the rims so both need replacing, and once when the electronics gave up, probably due to constant immersion in frozen slush under the bicycle and not drying out at night in my unheated garage. Mark has lifted the controller above the crankcase to see if that is better, it's less elegant but should be better protected from the slush.
I don't use goretex, just wear a base layer and breathable jacket down to about 2 deg C or a water resistant fleece when the temperature goes below zero. I have some climbing leggings I use when its really cold otherwise just some standard outdoor trousers with standard (cheap!) waterproof trousers when it rains or snows (cheaper when you rip them to bits if you come off!). Gloves - I use climbing gloves (trekmates) with liners when it goes below freezing.
My commute is 8 miles - usually 30-35 minutes - sufficiently short not to be a real pain when it is snowing and if it is really cold I just cut the power and on Sheffield's hills I warm up in no time!
One thing - it is, of course, usually dark, but the front light on the cytronex (60 lux cyo) is brilliant and shows road conditions well, even when the street lights are out.
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