If I had stayed working in the US from age 63 to 67 I would have received about US 150 more per month. Didn't seem like much
at the time, but it does moreso now. But I have also to consider that I've been retired for two enjoyable years longer and that
two more years in my then-job still depresses me to think of. Peace of mind, perhaps, is as important as more bucks, but once
given up the foregone bucks never return.... duh. Good luck in your decisions.