Mine are out all year round, even in the snow and ice - apart from farrowing to weaning. We're 800ft up, which is why I chose very hardy Tamworths.
Blonde, I have always loved Maremmas. I'll have one myself one day - even if it does have to get dirty up here! However, judging by the ones I've seen when I've been at Cruft's, I'm guessing the dirt would drop off quite easily. I have three Newfoundland/Bernese/collie crosses with long hair and one of the three has a soft and very fluffy coat which can be covered in mud one minute and clean the next. The other two have coarser, curlier coats and are a lot more difficult to deal with...!