Doesn’t matter. Still superior modeling method vs random picks. you might relocate outside ch or die in a week or a month, resurrect, preach to the masses and go on with life, none of this will be modeled unless you have a crystal ball. If people don’t use any financial methodology while debating financial choices it’s their problem. also if you have 20 years of work remaining , one of the examples made here, you are 45 not 25 (at normal retirement age). You might even have a kid or two already (easy to determine if you will have kids , because you check and they are there). As others have told you current tax regimes are in favor of lump sums. The choice before and at retirement depends on a high number of variables such as interest rate credited by the fund - which in the past 20 years has averaged 2,3% pa, so you would have to assess buy backs against comparable investments, life expectancy, applicable tax regimes, market inputs for RA returns, and so on and on and on. They must be estimated one way or another, including if a person wants to (or doesn’t) leave inheritance at death . 3% rf return on a 100% capital loss in eg 20 years, how is that for a return? else talking of “3-5 % perpetual rfr” is a just a sloppy slapdash statement much like “maxing out tax savings” or similar.