NVRAM, hands down. Just end any trepidation on battery leakage. For games with midnight madness, every once in a while set the clock to 10 PM.
I see so many boards damaged from batteries that leaked. It’s an expensive mess that can be prevented so easily. And there is just no need for it. Stop f$&king around and just install NVRAM. I’m saying that to everyone here. It’s the first thing I do when I get a new game.