How does Speedcash do its transaction processing in only 2 seconds.   POW of system of this speed would lead to alot of orphaned blocks due to latency in the confirmation process, thats essentially an inefficent process then that would not suceed long term.

If the system is using Proof of stake instead then its possibly more likely to suceed however I would defer to the longer term established coins like BLK or ENRG which I hold and would recommended as having long term developers involved in its prospects for 2018.

The POS system is far less energy consuming as an economic system which does matter for potential mainstream viability.   Also the orphan problem of many conflicting miners does not occur as much due to the POS system allocating staking in a queue like system based on capital value held on the network.  The users are essentially the miners also and the benefit to confirmation of transactions is mutually beneficially to long term holders, rather then POW mining which can become expensive for all due to excessive competition