I agree about using the dar in winter on all but the really bad days. Heavy salted roads is the main anti-use reason followed by very icy or severe storms.
The ACF50 is good stuff. Not a one coat wonder but topping up when needed is still required. Speay, brush, impregnated rag depending on the area. You can buy it in a "bulk" bottle. Mine is a 1l bottle. Small spray bottle, paintbrush, impregnated cloth kept in a plastic bag.
Yes the car gets dirty in winter but regular washing is fine. Regular use also keeps things running well,
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