I vote for ether is best transaction speed. As i have tried around 4 to 5 altcoins transaction including bitcoin . In that ether was best it took around 15 minutes, second Dogecoin it took around 30 to 40 minutes yes again i transacted from my one wallet to other wallet i am gathering my all doge earning in one wallet . third goes to bitcoin  . Ripple and litecoin i received i dint send to any one