I have the same predicament, having done tonnes of research on the pro's and cons, I haven't got a cover. Some people get on fine, but like Ekona says - unless you wash it every time, you risk the grime scratching the paintwork.
Same, so many pros and cons with using covers, i dont mind the washing part as i wash the car alot already and during the winter it wont go out very often.
The thought of putting a cover over the car outside through the winter would make me feel very uneasy especially with a black car. As soon as the first grit of the year hits the road my car is on my drive till we see the last of it, there is enough salt in the air living on the coast without the council adding to it. Through the winter every 6-8 weeks I snow foam, wash, wax and seal and seems to work for me.