I don't think there's an age limit on a denim jacket - I think it depends up how you look and the way you dress. If you are that older person who normally dresses classically, and has a shampoo and set - then, yes a denim jacket may look a little odd. I have a work mate who's in her sixties, and she tries very hard to look younger than her years, hair bleached, make up, nails done, likes to be tanned - She lives in jeans, leggings, with t-shirts or camisoles, wears trainers and toe post sandals - very much like Julia and to me they do rock a denim jacket very well. The customer I mentioned in another thread who's in her eighties would definitely look good in one as her style is very casual. You know your own style but there's no harm in trying, and a jacket is one thing you can actually try on in a shop, and with Q, there's always the 60 day mbg lol!