Caribou MF

Back in the early-mid '90s my then-girlfriend and I had a pair of matching Caribou Mountaineering mummy bags; one with the zipper on the left, and the other with the zipper on the right. We lived in Wyoming at the time, and later, in Tahoe, and it was just a fact that once you zipped them up together with two bodies sharing the same space, your temperature rating dropped a good 20 degrees F. We were into multi-day backcountry climbing and snowboarding trips at the time and used ours in sub-zero temps on multiple occasions, for example, even though individually they were only rated to around 15F.

WM has 3-4 "semi rectangular" models rated from 40F to 25F. "Only bag I know that no one has ever complained about being cold." I have a non-semi-rectagular, WM 40F bag that prompted my complaint around 50F. But have used it as low as 25F wearing supplemental clothing. Nice stuff; not necessarily worth the frightening price.

Western Mountaineering mummy bag. I do a lot in shoulder season and these are very warm for the weight

I am a cold sleeper too. And I’m embarrassed to admit, I could afford a western mountaineering bag. It was 0°. And I’m 59 and I got the 6 foot six version. Giving me tons of down to snuggle into. I actually use this bag way more than just the winter and I’m always toasty warm.

Western mountaineering. I get cold easily even in the summer in Colorado at high altitudes. I also snow camp

Don’t forget to get a really big bag one that goes way over your head. It’s just so cozy.

It really depends who you are. I can shiver on a Colorado summer night at 11k. So I spent 2lbs on a western mountaineering bag. I love it.

Western Mountaineering, Feathered Friends or Marmot for bags. Enlightened Equipment, Hammock Gear or Katabatic for backpacking quilts. Not cheap but quality and comfortable.

I've been a quilt user for years, but if I were looking for sleeping bags, I would go with either Western Mountaineering or Feathered Friends. You absolutely get what you pay for with either brand. Awesome quality.

There isn’t really an absolute best, but I like Katabatic for a quilt and western mountaineering or feathered friends for a bag. I prefer quilts down to around the low 20s, bags below that. Having a pocket in your quilt for a sleeping pad seems silly to me.

Good pad. Stick with that. Edit: (I forgot about the Nemo eclipse. That's something to look at. I don't think they're ready to ship yet. I don't know that factually. I think they're officially going on sale in march. REI was doing pre-orders.) Someone mentioned Western Mountaineering. That's the best. But they're expensive. I don't know if I'd recommend it for a beginner. I have one and it's totally worth it. If you know you're going to be out there, then maybe eventually you want to make that investment. In general about sleeping bags look at the EN or ISO Comfort rating. If they don't have that, you probably don't want it. That's an incorrect statement. Because even some top brands don't necessarily publish that for certain bags. In which case you just really need to look deeper into that bag. To give you a specific example, Western Mountaineering has EN number is published on a chart under their faqs. But that only goes down to their bags that are about zero rated and above. That doesn't mean that they're cold weather bags are crap. The exact opposite actually. But a lot of budget brands are throwing a temperature rating on there that may be more related to the extreme limit number which is survivability and you'll just be cold. If you want to look at the difference between the comfort, limit, and extreme limit rating, you can. But just stick with comfort. Maybe build in an extra 10° from what you actually expect to sleep in. That's a heavy tent. You can save a lot of weight there. Let me offer a specific alternative. Durston Xmid 2. It's a trekking pole tent. If you wanted to try trekking poles, this is a great way to save weight. If you don't want to use trekking poles, Durston sells ZFlicks poles. You'll still be significantly lighter than the Half dome 2. R/durstongearheads Naturehike is a budget brand with tents you can look at to see if one would work for you. You'd save money. And probably can come out a fair amount lighter. Check out r/ultralight. I'm not saying you should go full ultralight. But if you're going to be backpacking, save weight where you can.

Western Mountaineering has sleeping bags that you can order with one being right zip and one being left zip. And then you just zip them together. But I'm going to be honest. I don't know your friends and family. That's not something I would put on a wedding registry. And I don't mean I wouldn't put sleeping bags on there. I wouldn't put Western Mountaineering on there because it's so freaking expensive. I have one. I bought it for myself. I'm okay with that. I'm just saying I wouldn't ask anybody else any kind of obligated way like a wedding registry to spend that much money on me. What I'm seeing from the comments is that there are probably other brands that can do this. I just don't have a more affordable specific recommendation. So a little research might turn up a good result. I know a lot of brands are going to use zippers from similar suppliers. But my sort of guess is that you'll be better off finding a brand where they specifically state their bags zip together and then get two from them that you know are compatible.