Debating getting a pair of chinchillas, but I have some questions

I've been debating getting a pair of chinchillas for a few months now. I had a pair of rats for about 2 years that were great, but I don't think I can handle another pair dying in 2 years. It's just too quick for me. And yet, one of my problems with chinchillas is that they could theoretically live for 20 or even 25 years, from what I've heard. I'm not sure I'm ready for that kind of a commitment to be honest, so if I get any, I would rescue an older pair (5-10 years old maybe).

One of the other reasons I'd adopt an older pair is so that I'd be aware of their personalities going in. I'm used to dealing with rats who didn't like to snuggle too much and preferred climbing all over me instead, but I'd be lying if I said I wouldn't prefer a more snuggly animal. I've heard that a lot of chins don't like to snuggle, but it sounds like some rare ones don't mind?

Also, how much do the chinchillas like to burrow? I tried using fleece liners with my rats, but they insisted on ripping them to shreds and tunneling under them, which sort of defeats the purpose. I definitely preferred using fleece because of the reduced cost, but if I have to use other bedding I can deal with that.

Is it possible to litter train chinchillas? I've heard they poop a LOT, but I'm more concerned about the pee. If it's possible, how easy would it be to litter train older chinchillas if they don't have any experience with it?

Ideally I'd want to interact with them most around 6-10pm. Is that acceptable, based on their traditional sleep patterns?

If I get chinchillas, I'll be their last owner. I'm not the kind of person to just decide that I'm bored with them and that I'll move on to something else. I just have no experience with them to begin with, and even 10-15 years is a long time to have a pet. I want to make sure I'm going in with as much information as possible before I make a decision.

Any other advice for me? I already have a double Critter Nation from my rat ownership, so the cage isn't an issue.