I prefer nets. The only down side to them is that it's easier for a horse to get a shoe caught on them
I prefer hay nets as I find hay bars could be hard on a horses teeth, and hay nets also prevent more wastage and allow them to eat for longer as they can only take small bites at a time.
For those who chuck the hay out, you can either weight it or net it and tie the net inside the haybar. Slows them down and keeps that good eating position for head and neck
I prefer nets or hayracks as the horse would pig out her hay too quickly but the boy has a plasters bath for his hay :)