Care to share the juicy details on the rates you got and margins you made? If it was in the most recent run-up, then it was likely well over 12% on margin.
My last refi was in May of 2015 when I cashed out $60k at 4%. The S&P has had an annualized return of 5% (in nominal dollars) since then, including dividends.
I also pulled out $45k in July? of 2011 at 4.5%. The S&P has had an annualized return of 10.1% (in nominal dollars) since then, including dividends. That difference is enough for a new, not-quite-mustachian, car or a handful of mustachian, used, cars.
Meanwhile, inflation goes up by 2.2% and my mortgage payment stays the same (cue Matthew McConaughey in
Dazed and Confused).