For many years I have been using two jackets:
* Mountain Equipment Morpheus (50D/70D) for winter mountaineering: easy winter soloing and walking. I used it during the summer where I would be wearing a heavier rucksack (camping, bothies, etc.)
* Montane Aero Event Pullover (15D) for decent weather summer walks and rides. It's half the weight of Morpheus, but not the most durable - though it survived 3 years already!
The Morpheus is getting quite worn out now (bought second hand 4 years or so ago). I bought an Adidas Terrex Feather Gore-Tex Pro jacket, which is just over 400g and I can only assume 40D (minimal requirement for Gore-Tex Pro). I am now having second thoughts whether heavier rucksack and general winter abrasion won't damage it too quickly? Or maybe the Morpheus was an overkill?
P.S. The reason I bought the Adidas jacket was the price - £70 brand new from a non-outdoors shop. It has all the bells and whistles I needed and I am happy with the fit. If I don't find it useful for winter stuff, I can always use it for summer/pub.