The two-way contract is still a massive experiment around the NBA. Nobody quite knows what to make of it yet. Some teams used it exhaustively, others struggled to find its place in their plans. It was a good way to develop players and keep quality players close to the NBA but there are obviously limits with the 45 days a player gets with the NBA team.
It certainly has value when the team faces injury. But that was a bit of the confusion with the Orlando Magic and their two-way guys last year. Adreian Payne was cut from the team in January amid the allegations at Michigan State.