I had her for about 2 months but change my bags frequently. I love the size, strap drop, easy access and the fact that the middle doesn't smoosh in when worn with the long strap (looking at you, Sophia and Lindsey)
If I were to pick one out of my Coach collection it would be Isabelle. I can carry her so many ways and she fits what I carry on most days. If I picked out of my whole collection it would be a much harder choice. Lol. I don't even want to think about it.
I've paired down my collection quite a bit so I think whatever I own is my absolute favorite. That said I guess the most easy to use bag I have is my e/w pink/red saffiano tote. Roomy, light and easy to carry, and zippered on top.. It's def the most practical.