I've stayed in a total of 11 apartments on 6 different trips. Stays have ranged from 5 to 8 nights. Eight of them were with my husband and the last 3 were on my own. My hotel or B&B limit is 4 nights. Anything longer and it's an apartment for me.
On the whole, my apartment experiences have been positive.
There was a VRBO that wasn't very clean when we checked in and required that we clean the place before leaving. That was a total surprise. Nowhere in any of the information on the place or in our correspondence with the owner was this ever mentioned. It would have been a deal-breaker if I had known.
My best experience was a beautiful place in Venice with a view of Cemetery Island and a fabulous kitchen. The owner lived on the next floor up.
I like apartments because there is no time limit on breakfast. When my husband and I travel together we like having a bedroom with a door that shuts and a bathroom that is not ensuite to the bedroom. That way he can sleep late and I can get up early and we don't bother each other.
I'm not so naive as to think I'm living like a local when I rent an apartment, but I do like shopping nearby. And I just like being there. When sitting staring out the window from most of the apartments I've rented, I thought it was much like sitting at a cafe watching people go by. I could definitely be a nosy old woman doing that from above -- especially if there is an elevator.