>>1829383I have a Hotcore R-300 for winter camping, a Marmot Trestle for fall/spring, and a cheap MEC summer bag I bought 20 years ago for around $80.
I'm guessing you're American, probably best to just check REI and see what they have, I've heard their warranty is really good and haven't heard anything glaringly bad about their gear. MEC is basically the REI of Canada.
I would rate my Marmot to be comfortable down to about 40F, but it's definitely too hot to use in the +65F range.