I have mainly been using a Lowepro LP36466-0WW Passport Sling II Camera Bag (Mica/Green) with my micro four thirds setup. It isn't as bulky as their Urban Photo Sling 150 (which is very similar to the bag the OP described) because it has less padding.
I mainly wear it in sling style, since it does look a lot like a murse if worn over the shoulder. However, you have the option to wear it either way. One of my favorite features is that the bag will unzip on one end and expand. This gives you more options for carrying more or less gear.
As others have mentioned, it is hard to find the perfect bag because I may want a backpack for one day, a shoulder bag for another, or a sling for another. Also, the amount of gear can change from day to day.
I mainly wear it in sling style, since it does look a lot like a murse if worn over the shoulder. However, you have the option to wear it either way. One of my favorite features is that the bag will unzip on one end and expand. This gives you more options for carrying more or less gear.
As others have mentioned, it is hard to find the perfect bag because I may want a backpack for one day, a shoulder bag for another, or a sling for another. Also, the amount of gear can change from day to day.