I love the gen movements, reverse datewheel direction, perfect date placement, feel of winding, quietness of the rotor, etc. It is a real luxury if you can afford it. But the issue for a 1680 is always as has been said previously is that you will be well above 50% of the cost of a gen at which point I am saving my pennies for a gen. Now if you are building a 1665 or Red Sub or anything which would normally sell for $7k or more it makes a lot more sense to me. And of course the best part about gen parts is that you can always sell them for what you paid (if you bought intelligently) and get your money back that way if you want out.