Hard to choose one.. 3940 1st series or 3940p, 2526, 3428.. Dream one and done pieces. I would choose comfort and ability to just blend into the wrist over a thicker Perpetual calendar chrono or manual wind chronograph. More of a daily wear. The 5110 series (any) is the last of the great Patek for me and a serious one and done contender. Any of these a wonderful companion to go through life with..