Originally Posted by
Another Kevin
This is one that I sort of feel qualified to answer. As a clueless weekender, I've always hiked on a fairly stingy budget. If I were planning a Big Hike as a Life-Changing Event, I might be able to justify to myself dropping a few grand on gear, but since it's just the occasional getaway, I try to dirtbag as much as possible. So from that perspective, let me observe:
In the East, virtually everyone's first sleeping bag should probably be a not-too-expensive but not-too-heavy 20° down bag. It's a compromise in a number of areas, but a great thing to get you started.
It's too hot for summer, but you can always sleep on just your pad and pull just enough of the bag over you like a quilt.
It's not nearly warm enough for deep winter, but in 'shoulder season' or in the Southern winter you can sleep in a fleece suit, beanie and gloves, and not shiver.
It'll be heavier and bulkier than a really expensive bag of the same temp rating, but by the time you really want the ultralight bag, you'll have a pretty good idea what you want to buy. And what you want to buy may be a different temp rating, or may be a quilt (or TQ and UQ combination for a hammock). If you're asking this question, you don't yet know your hiking style. (You may know your aspirations, but that's a very different thing.)
The Kelty Cosmic, the REI Radiant (or Igneo), the EMS Simmer Down (or Mountain Light) are all in about the same price and quality range, and all three have been around for a long time. A lot of us have started out with one or another of those, and never got around to replacing them (although many of us have added on dedicated summer- and winter-weight bags, and maybe even a mountaineering bag). I seem to recall that even PMags takes his Cosmic out during Spring and Fall. I know that I still have my Radiant. Yeah, I could spend a few hundred bucks and get something fancier from Western Mountaineering or Feathered Friends or someone, but I always seem to have something better to spend the money on, even when I'm spending on gear.
I personally wouldn't go below the price tier of those bags because you then start getting into stuff that either is ridiculously heavy or else isn't true to temperature rating. It's far better to try to pick up something used. There are a lot of people who get geared up, try backpacking once, and decide that it isn't for them, so if you live near a trail, you might be able to make a find at a thrift store or on Craigslist.
As far as pads go, the way to get maximum versatility on a budget is to start with something like a Z-Rest or Ridgerest - a better-grade foam pad. (Although a blue foamy would get you started, they don't last quite as well and they're heavier.) As you get into colder weather, add an insulated inflatable pad to your collection, and in winter, simply carry both. I've gone to negative-single-digits by bundling up in all my clothing in a 0° bag on top of a RidgeRest and a ProLite, with my puffy jacket spread on top of the bag over my core. With that combination, I can stay toasty at -5°. If your foamy doesn't have a reflective layer, put a car sunshade between it and you.
If you are planning the Life-Changing Big Hike, sorry, I don't have a lot of knowledge in that area. I don't know if the recommendation changes for that.