I've bought a few things from J&O over the years (back since they were the only Toronto retailer that carried Shopbop). It's definitely a luxury designer store, so while I only stop by a couple times a year for items, I find that my shopping experience is always a positive one.
I think the biggest draw of J&O is the customer service. Earlier this year I picked up the last pair of Acne pistol boots at the store. When I got home I noticed there was something off about the leather on one of the boots. Chelsea was extremely helpful and because they didn't have any in stock, she had a new pair directly from the manufacturer for me within weeks.
Every time I have been there to try something on, staff are incredibly knowledgable and always make great suggestions or pick out pieces I might have overlooked.
Prices are what you'd expect for their merchandise. Could you get it online for cheaper? Yes, probably. But I find that the overall experience in being able to actually try things on while supporting a local business are more important than saving a few bucks.
The only downside to the store are the hours. Last I checked, they closed at 6pm which might make it hard for people with 9 to 5 jobs to shop in the evening.