Fair questions, all very important.
For me it was always the love of the job I miss. I absolutely loved my job. I would still be doing it today if they hadn't forced me out. I fought the decision till the 2nd last day. I was never going to stay till 65, but I wanted to leave when my mind or body said so. But after 23 years and many injuries later I was deemed un-deployable. So they offer you early full pension, a financial incentive on top to 'take the offer' and they play it up -you can retire at 45, your so lucky.
Not really, as I started in early 20's, I still have put in the time. It was very hard on me to leave. I loved the camaraderie, the challenge, the intense pressures, the thrill I guess. Even though the last 3 years I was overseeing training courses instead of active duty.
As for expenses, savings and costs, again dam tough choices to make. We all want financial security, but is it at the expense of enjoyment. My father had money, could have retired at 59 with full pension. He chose to stay around till 70. He said he loved his job. But 3 years later he was gone. He admitted at the end it was about the money, which didn't make sense as they had a lot of it, and no house or car payments, minimal bills, so that excuse was not a good one. He valued security over his life, and in the end all the security meant nothing.
I think that is the eternal question for people at or near retirement. Am I good? Will I make it, if so, do I leave now or hold out for more. Sometimes that bit of greed we all have stops us from living our best life. Frees us from the slavery of the 8-4 and gives us the greatest gift ever...time.
Now, that we are retired early (I did at 45, her at 48) we realize it was the greatest thing. We have done so much in the 10 years that we would only be possibly starting about now. That leaves us so much time to do so much more. The experiences are worth it.
But I understand you query. Its tough. My wife fought with herself for about a year on what to do. It wasn't the money as her pension started paying out immediately as did mine, but it was, if she kept working we could save more. That ever lasting desire to get a bit more, protect your nest egg, etc.
I guess its up to you. All I can say is my personal opinion. If you are good and feel you will be, enjoy your life. Live simply, live well, live healthy, live happy...I guess it comes down to-what of the 2 options will make you the happiest?
Best of luck...