I agree with a pressure cooker. You can use an Ninja Instant Pot or something similar and get the same broth in 2 hours.
I've read bad things about contaminants in the ceramic liners in slow cookers. I think it's different heavy metals. Not something you want to add to bone broth you're using to rebuild health.
Be careful if you have any issues with histamines or oxalates. Slow cooked bone broths are high histamine (pressure cooking helps cut this way down). If you have issues with oxalate the glycine in bone broths can add to oxalate load in the body. Overall bone broth is super healthy but contraindicated for some people.
I don't know if I have issues with histamines or oxalates. All I know is that no matter what I eat, I constantly break out in acne. I tried to do a 2 week long bone broth fast (I didn't even make it a full week) as an elimination diet type of thing. During the time I had nothing but bone broth, even though it was a processed bone broth, I had no break outs for the first time in my life. I couldn't keep it up though because I wasn't getting enough calories and feel super weak and tired all the time. I tried doing just bone broth + raw milk, with a blue rare seared steak every so often, so I could get enough calories, and then coffee. But once my cycle came up again (pms with really really bad cramps as well) I broke out horribly bad. With cystic acne which I haven't gotten in a long time. I'm still drinking tons of bone broth and trying to limit what I eat but I'm feeling like crap, weak and shakey. One good thing since I started drinking tons of bone broth though, is my nails seem a lot stronger and don't break as easily. I like that a lot since I like to grow my nails out long, but they always break all the time.
I've tried eliminating so many things yet I still break out all the time. I did fully raw paleo, which helped the most, since I started it from a SAD diet, but I still broke out. I tried the WAI diet(twice), which was fully raw as well, and it helped a lot but still never fully healed. I tried eliminating dairy from my diet, still broke out. I tried eliminating plants from my diet, still break out. I'm mostly carnivore right now, eating mainly bone broth, egg yolks, raw milk, raw cheese, raw butter. Still breaking out. When I eat steak, which is only a few times a week right now, I season with garlic and pepper, and lightly sear it because I don't like cold meat. I used to sear it in butter, tried not searing it in butter(or anything), still break out. Right now I'm trying to go a week without any sugar, besides the sugars in raw milk (+cheese and butter), to see if that will help. Limiting my dairy carbs to keto levels. I'm still breaking out, 6 days in. I'm on day 4 with no steak, in case it's the garlic/pepper/searing that's the problem, still breaking out. I miss my coffee with sugar. I'm tired all the time. I hate this. I wish I could just be a normal human being and eat normal food without having all these problems. I don't even need junk food, I just wanna eat steak and eggs every day with some raw milk to drink. Coffee with sugar every so often. Maybe a burger bowl once in a while, with raw onions on top. I miss fruit. I don't need veggies or grains, never liked them, don't eat them. I want some sushi, too. Sashimi actually, I don't need the rice, just give me some raw salmon and tuna. I'm tired of all of this, I'm about ready to just give up on life and live with being ugly and in constant pain and depressed because I look more like a spotted fricken hyena than a human being. cause oh yeah I got tons of spotted hyper pigmentation acne? scars all over my body as well. maybe haha, maybe going vegan would actually be the thing to cure me. that would be the one thing I still have never eliminated yet, is animal foods. Might as well be fruitarian then though, because I hate veggies and grains.
Anyways, long story short, I wanted to try a bone broth elimination diet but the bone broths in the stores are all high in protein and low in fat and low in calories, plus have a bunch of random veggies mixed in, so I wanna make my own bone broth with only raw marrow bones that still have the marrow in them, so I can get all the good fats and stuff from the marrow and get more calories as well, plus some raw apple cider vinegar as an acid to help break down the bones. But I don't wanna overcook it so I just wanted suggestion on a slow cooker that actually has a low enough temperature of like 100 or 150 degrees (F) that isn't too expensive, cause all the cheap ones I looked at only had settings of "low, medium, high, warm" and don't actually say a temperature on them.