I think the best and safe for investment is to build your own mining rig this is much better than investing online except for investing more in bitcoin and hold them for a long time..

Base in what i seen to the site you give i can only seen to option investing tab crowdfunding platform and forex broker and i see the little list of ponzi's but almost all are marked as scam
The good thing in this site you see new sites posted there with reviews..

Anyway i can be still be safe if honestly wanted to invest  mining altcoin with your hardware is the best option as of now base on my own experience..