It`s surprising how different these two watches are. The 5726 a rather bulky sports-watch whereas the 5740 is the elegant nautilus… Both cool pieces anyway
The 5726/1A-014 has the same blue as the 5711/1A-010. The 5740/1G has the same blue as the 40th anniversary 5711/1P. The special client 5711/1P has a little different blue to my knowledge…