I had one, we lost her 2 years ago, she was lovely but was quite barky, she was incredibly loving and loved all people.
No back problems but did develop diabetes when she was about 10, so we had to inject her with insulin twice a day.
We had 2 other dogs at the same time, mostly they all got on fine, but there was a bit of competition between her and the great dane as they both wanted to be head of the household.
Never had any problems with her wandering, and when out on a walk she would never leave our side even when off lead. House training was a whole different story, she was so stubborn and just wouldn't go outside if the weather was inclement. She would sneak off and do it secretly, although we never saw her do it, but would find a little puddle behind a door.
She was funny, clever, cheeky, stubborn, loving, faithful, needy and probably the most difficult dog we have
I would love another but my daughter who lives close by said all the house prices would go down in the local area if I did.