Consider layering your sleeping bag system. I have a synthetic overbag and down innerbag. Works well for me. More versatile than 1 big winterbag. Synthetic outerbag is where the condensation ends up, and keeps the inner down drier. I use an MEC synthetic overbag, a Feathered Friends down innerbag (which is really a "half bag", only goes up to my armpits). When really cold I sleep in my down jacket as well. I've found this to keep weight and cost down, and it works in a range of temperatures.
I recommend a 3 person tent if you are going to have 2 guys sharing on a regular basis. It’s a bit extra weight but nice even on solo hikes.
When I did more winter camping years ago I had a synthetic bag but in recent times have gone with a down bag (now down quilt) with a small down blanket that I put inside when need that little extra. I picked the down blanket up at Costco a few years back but have seen them there since then. Main reason I use down is that I do more summer/ fall hiking than winter camping these days.
I just went through all the confusion of buying a new tent. I ended up with a teepee style so i could add a stove jack and stove. I have only used it once but it was in the snow and i am more than happy with my choice. Its made over seas and cost about 1/4 the price of the exact tent with a name brand on the label.
My order of importance is bag, tarp, tent. I have a a -5 bag that I’ve owned for a number of years and it’s nothing special, but the cold weather keystone is my old army surplus down liner. It also has a cotton liner that goes inside of it. I have slept tentless down to -30c comfortably. The second thing is having a good tarp. It easily doubles as a tent and if weather gets sour you aren’t limited to your tent as your only dry area. Lastly the tent. It’s nice to get out of the wind, and is great for keeping the bugs out, but for general survival... meh. You just don’t want one where your gear is going to be pressed up against the walls, so go big.
I'm a Mountain Hard wear fan.
MEC tents come at a good price but the design is sometimes not at par with other brands.
There are different options. I have a Big Agnes model discontinued which is roomy for two and good in snow. Go to stores and check tents out. They need to work for you in the environment that you are using it for.
As for sleeping bag down all the way and a synthetic overbag if needed for very cold temps. A good 4-season sleeping pad goes a long way for warmth.
Ive been looking at backpacking tents for next season, and then started looking at combining a goretex bivy sack with a Neoair pad, synthetic -9C bag, with a DD Hammock 3m x 3m tarp. With all the tiedown points on the tarp, it can also be configured into a floorless tent for 2 using hiking poles (see multiple Youtubes) .
i guess its personal preference re tent vs bivy/tarp....anyone else choose the bivy/tarp route? Seems a bit more versatile for similar weight.
found this military issue goretex bivy made by Tennier https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Ya ive read some bivy reviews that discuss condensation problems, but moreso when one is breathing inside the zippered up bivy, and also with bivy's that were not breathable goretex. I was thinking of leaving the bivy open at the head, keeping my breath outside, wear a toque, and combining the tarp overhead for weather protection.