I'm on the fence regarding Roth conversions. Currently, we're still in a very high tax bracket due to DW still working and some megacorp options I'm selling. But in a couple years, we will be solidly in the 15% bracket, with 15 years to do conversions, until RMD/SS put us in the 25% bracket. All that sounds like a classic case for converting.
But the more analysis I do, the more hesitant I become. Most likely, we would never take any Roth withdrawals. So, in our lifetime, the impact is negative... taxes paid, plus the associated growth hit, exceed the tax benefit of lower RMDs. But of course, there is a huge shift from taxable and tax-deferred into tax-free Roth, which will benefit our kids. But even that depends on their tax bracket at the time, tax code at the time, etc. In theory, the kids will be FIREd and in the 15% bracket when we die, which is a more-or-less breakeven scenario for converting.
Too many if's. Too far in the future. Our retirement preparedness is pretty solid, but not so "rock solid" that I'm ready to start prepaying tax for the kids at age 53. We're way too early in ER. I'll re-evaluate after a few years.