@nerdman Unless you're buying some server grade equipment that has quad-channel memory, just stick with 2x16gb. If you grab a motherboard with 4 slots it will also leave you options for upgrade in the future.
If you're not sure if you'll be willing to invest money again in the future, especially since it might involve changing both motherboard and CPU, it might be better to "future proof" and grab the better components. Or even if building a PC isn't fun for you, and you don't see yourself spending time doing this research again soon, also try to "future proof".
That I do. Sometimes too much. But that's a story for another day.