I think the first one is at 3.5 or 4 years old, the second one is looking like 3 years old and the third one is in need of some lead at around 5 years old. The last one is still youngish but I would take him on a cull hunt not my yearly big un.
If I had my choice I would shoot 1 and 3 for record. They have spread their genes for several years. As for number 2 I would wait on him another year so he gets a larger body.
This is just my thoughts.