Top Bar hives are fine:
IF
1. You ignore the rubbish posted by the Natural Beekeepers of this world: mostly they live in places where any fool can overwinter bees in a hive that has holes in it and expect them to survive. I did my research and amended the designs. and insulated.
2. You don't want much honey.
3. You like lots of hard work to get a little honey.

I am converting to Langstroth