The Complete Walker is a great read and packed with information. Colin Fletcher had a guy by the name of Chip Rawlins co-write the latest version. Both guys are great writers and have differing opinions on some gear and technique, so it makes you think a little about your own style and what may or may not work for you.

I've been a backpacker most of my life, and dabbling in the ultra-light thing for a couple years now. It's not for everyone that's for sure, and I still can't fully dive into it. Mostly from this tiny fear I have of the unpredictable. I could go on, but I'll get to you question.

Waterfilter: I, like Duct tape, carry both. I hate the taste of the chemicals, but they're a back up. I don't have the lightest or fastest filter, but it's bomb-proof. I'm ok with the extra weight and bulk for the instant gratification in clean cold water. If you're concerned with a virus and don't want to carry both, you can buy filters with a chemical cartridge for a bit more $$ and bulk. My opinion, that's kinda overkill in the States.

Knife/Multi-tool: I used to carry a Multi-tool. In 7 or 8 years, I never once used it. Two years ago, I left it home and haven't looked back. A small well made lock blade has been plenty for me, but I've recently started carrying a fixed blade as well. Any gear servicing I need to do can be either be done by hand, blade, duct tape, or I don't need it to survive anyway.

Bottomless Sleeping Bag: I've tried them, and I have friends who like them and friends who don't. For the most part I'm impartial. I'm ok with the theory, but I think sleeping bags are very personal. Bottomless aren't for everyone and if they don't fit right you will absolutely get cold spots at the edges. More like... drafts really. I personally prefer full insulation because it's better to use as a blanket. I realized this one cold night when I had to fit my 85lb Lab under my bag with me.

Those are my thoughts anyway.

m