>>2755789All synthetic ~25° bags will be bulky. The cheaper ones will lie about their temperature rating. And reviews are always subjective; some people really aren’t as cold or warm as others claim to be using the same bag in the same conditions.
Best bet is to use your own judgement. Get a quilt instead of a bag. Add a liner.
I saw pic on Etsy. They’re claiming 800fp down, 26oz total weight, 10oz of insulation, and 30° comfort rating. It’s a very basic rectangle and one end sewn together to form a foot box. The inside is some kind of reflective Mylar. It really doesn’t get much simpler. The brand/store is HangTightShop and the model is a HotFoot Top Quilt. It’s $95.
But it might be totally misleading. Down retails for $25 per three ounces, so 10oz retails for $83. Maybe it’s not homemade (like most things on Etsy) but is just mass produced in China. Who knows. I’ve seen down puffies in TJ Maxx for like $20. So cheap down is definitely real, and the overall quality is what you’d expect (shitty), but the warmth and compactness are a great value.