luno is an exchange, not a real wallet. GDAX has 0%-0.25% fees, while coinbase is 2% or smth like that.

Fore real bitcoin wallets, you can set the transaction fees yourself, but the probablitiy of the transaction being processed is higher the fees are. All wallets are equal in this regard, and what will influence the transaction fee is the state of the network, not the wallet you're using.