Sleeping bags and mats - If you aint comfy you aint gonna make it
Nothing can destroy a good adventure like not being able to sleep. Not enough mat under you, or not enough warm around you can both lead to a miserable time at night. Adequate sleep is not only enjoyable, but safer. A well rested and warm person is able to make better decisions the following day, able to hike with more alertness and sure-footedness, and even more importantly, is MOTIVATED to keep hiking!
Everyone is different, and there is no single best solution to everyone's sleeping enjoyment. Best I can recommend is to actually get inside a few sleeping bags - and compare their WIDTHS to how much room you like to have when you sleep. Some folks can sleep in a tube, others like myself, need a bit of wiggle room to comfortably fall asleep.
Synthetic and Down both have advantages and disadvantages.
My nice $300 down 35* bag (hidden under my MLD Superlight Bivy (all black and 3rd from Right in the photo above)) was a great 1.5 lb bag for shoulder season camping and the cold weather start of my AT thru-hike. However, when I got into the hot and muggy sweltering mid-summer, I switched to a cheap 1.5 lb synthetic 55* bag that only cost $60 and used it all the way until the end of the AT. Years later, I ended up using a 30* down zippered quilt (no hood) for all 2,650 miles of the PCT, from 20* and snowing to 70* hot evenings and sweltering heat. HOWEVER, I am not you, and just because something worked well for me or another person, doesn't mean that your body runs the same temperature spectrum that they do, or that you like to sleep like they do.
Read up a bit on the benefits of Down versus Synthetic Bags and then go try some out if you can! If you can't try any out before hand, err on the side of a slightly warmer bag until you get to know your body and how cold you really get. For younger kids or accident prone older ones, a synthetic bag is heavier and will take up more room in your backpack, but it is much more forgiving when wet and not handled gently, synthetic bags also tend to be cheaper.
Everyone is different, and there is no single best solution to everyone's sleeping enjoyment. Best I can recommend is to actually get inside a few sleeping bags - and compare their WIDTHS to how much room you like to have when you sleep. Some folks can sleep in a tube, others like myself, need a bit of wiggle room to comfortably fall asleep.
Synthetic and Down both have advantages and disadvantages.
My nice $300 down 35* bag (hidden under my MLD Superlight Bivy (all black and 3rd from Right in the photo above)) was a great 1.5 lb bag for shoulder season camping and the cold weather start of my AT thru-hike. However, when I got into the hot and muggy sweltering mid-summer, I switched to a cheap 1.5 lb synthetic 55* bag that only cost $60 and used it all the way until the end of the AT. Years later, I ended up using a 30* down zippered quilt (no hood) for all 2,650 miles of the PCT, from 20* and snowing to 70* hot evenings and sweltering heat. HOWEVER, I am not you, and just because something worked well for me or another person, doesn't mean that your body runs the same temperature spectrum that they do, or that you like to sleep like they do.
Read up a bit on the benefits of Down versus Synthetic Bags and then go try some out if you can! If you can't try any out before hand, err on the side of a slightly warmer bag until you get to know your body and how cold you really get. For younger kids or accident prone older ones, a synthetic bag is heavier and will take up more room in your backpack, but it is much more forgiving when wet and not handled gently, synthetic bags also tend to be cheaper.