I'm a BTCP fan.
It is my first "bigger" investment.
I'm planning to switch some of it to Steem to power up.
Haven't heard of Manna.
I can see that it's ranked low, and barely has any volume.
But, if it gets on a bigger exchange, its' price can really take off.
Good luck in that.
The tokens are offered free too...that is why I put the referral link at the end of my post.
It is a basic income token...designed to be given to people as a basic income....each week tokens show up (on Thursday).