This Guy can be useful in a tight spot, but as was said before me he can't control the board like original Masticore, this guy does a concentrated blast of 3 each turn which can be good for taking out bigger creatures. Original Masticore has the option of hitting small things which you might not want to waste 3 damage on. Of course original Masticore has an activation but the "new guy" costs more. Seems to even out.
Both seem like valuable assets to decks but in my conclusion , Razormane Masticore is more of a type 2 card. Of course you could say that about Masticore when it came out in Urza's Destiny , but then again Urza block was never a good example of type 2.
As for the mana problem of it being 5 , guys this is type 1 , one extra mox or mana producer can take care of this.