Ascent AcII

I've been really happy with my Sea to Summit Ascent. Taken on many backpacking and camping trips.

Nice. I can't remember if they are on EV. I got them on Prodeal when I worked at REI. I use the 15 version, it's been great. Not too restricting. Couple nice small features too, like the phone pocket and the snaps so you can sleep with zippers down and arms out but still closed up. Plus a foot zipper for extra temp control. 

Tents: if you're going with friends, share a tent as often as is comfortable. Really helps with the weight when you can split up the components. MSR Hubba and big Agnes Copper Spur are two well regarded tents you can get at REI. Easy to set up and slightly more durable than some ultralight focused stuff. Sleeping bags: Find a shape you like. Not everyone feels comfortable in a mummy bag. Seat to Summit (Ascent) and Nemo (Disco) have some alternate shape bags that are really good. Highly recommend down over synthetic if you can afford it. Better in every way, just make sure to have a waterproof stuff sack. Doesn't work when it gets wet. Cookware: depends on which stove you're using. For something cheap that is still pretty light look at the Stanley Adventure nesting set. Long spoons are nice! Pick up a water filter, Katadyn or Sawyer Mini. A small pillow is worth the weight. Some say to sleep on a jacket or sweatshirt or your other sets of clothes, but better neck support really helps. It does for mem, anyways lol. Wool socks and underwear. Pays for itself with comfort and anti-microbial properties. Also, you JUST missed the biggest sale of the year, so...bummer.

I've used both the Kelty Cosmic Down 20 and the Sea to Summit Ascent series. For the price, the Kelty Cosmic is honestly hard to beat if you’re on a budget. It's warm, decently light, and has held up for me after a few seasons already. The Sea to Summit is nicer overall with better materials and features, but for most backpackers starting out, the Kelty does the job nicely and won't break the bank.

Oh, totally get what you mean about versatility, being able to open it up quilt-style is a game changer on warmer nights. I’ve definitely done the “foot out of the bag” dance too many times before I discovered those features, haha. Have you checked how the zippers hold up over time with the Sea to Summit? That’s one thing I was a bit nervous about, but so far mine’s doing fine.

Sea to summit ascent and trek (older version) is what I have. I got the long versions in each flavor. My wife has the female version. They're so good IMO that when they were being discontinued we picked up extras when REI had them for 50% off. I'm likely not going to be buying new bags for a couple of decades now....

I have a sea to summit backpacking bag that’s 15° rated and once it’s in a stuff sack it’s incredibly small for a 15°. Coleman is basically bottom of the barrel, sleepover style, when it comes to sleeping bags, I’m surprised you aren’t freezing to death at night.

At REI? Probably just the sea to Summit. Cottage brands just do a better job overall. Here's a good start, but there are tons of other options. https://www.garagegrowngear.com/collections/quilts-sleeping-bags?srsltid=AfmBOop9T_mFgmquiOSKZQgg1443MbZ_HlewD5AHWCbOT52ZRMPPJVRi