I think it's better to invest in Dether because,
Dether is officially supported by Consensys, the venture production studio building decentralized applications and various developer and end-user tools for blockchain ecosystems, focusing primarily on the Ethereum blockchain.

Dether have a fantastic offering with the ability to make cryptocurrency and blockchain technology accessible to users around the world with very low barriers to entry. They are truly breaking barriers to global blockchain adoption by creating a fully decentralized bridge between fiat currency and cryptocurrency.