Rittenhouse Rye Whiskey. I have developed a minor obsession with Manhattan cocktails of late, and the right Rye is arguably the most important ingredient. Manhattans made with Rittenhouse 100 Proof Rye are the best that I have made so far. I have paid twice as much for a twelve year old Rye Whisky that is not as good. This has a great flavor and even at 100 proof, it can still be enjoyed straight. For the money, it is hard to go wrong with this one.