It depends on your location, and if your government does approved it
But here in Nigeria, the best for now is Binance being that the government has banned local banks from engaging in crypto related transaction.
Before the ban, the best wallet for storing crypto in Nigeria was Luno, but since it has no p2p trading platform which enables you to sell off your coin if you wish to, a lot of people switched to Binance.
But if you still want to safe s long term, you could still keep it in Luno and hope for a better move by the government I the years to come