I have seen that study and it has a lot of critics.
Here’s one with the exact opposite conclusion:
http://www.bmj.com/cgi/rapidpdf/bmj.38586.448704.E0v1.pdf
I’m not sure what the “right” answer is
True, there is no right answer, but on the surface I'm inclined to retire as early as possible if my finances and economic conditions hold up once I turn 55. Not to say I'll quit working altogether, but at least cut my hours back significantly and find something a lot less stressful that I would enjoy doing while balancing it with personal things that I have wanted the time to do.