I don't see 300 as it is today but this coin can easily hit 50-100 np, probably even up to 200. perhaps if it goes on more exchanges, we get more volume and people start using mnx as a way to gain passive income, the price of the coin will shoot up.
Why you do not see price higher than $300, makes sense to me, many other alt coins have surpassed this figure and they do not have rewards that MNX offer.