Let's assume you're on the hunt for a new victim to mangle, er, I mean pocket watch to fix. You find orphan movements, a Waltham and an Elgin. Both are approximately the same age, the same size, and have the same fairly high jewel count. One has pressed in jewels and the other has screw down jewels. Both are in sad shape with a broken staff but complete. Both are the same price (cheap!). With the exception of the broken staff(s) the condition of the other jewels/pivots, mainspring, and gear train are unknown. Which to buy? And why?