No point in having a bag full of stuff and trying to read directions in the rain at night in the cold in the middle of nowhere only to find out it doesnt work or you need another piece of the puzzle. I like to know I will be reasonably warm and comfy when I really need it. Thats why I take my bag out into the hills by myself to make sure stuff works before its needed.
The enemy of my enemy...... Is just one more set of targets to engage
I have had good luck with the butane lighters - even the cheap ones. That said, I keep several different fire sources in my survival packs and BOBs. But I have a $2 butane torch that we keep in the RV and use for campfires that has been refilled numerous times over 3 or 4 years, and still works like new.
Yes, try things before you rely on them. My butt pack on my web gear has a sealed package of 2 new Bic disposables, a Calibri survival torch, a magnesium fire steel and flint, some 0000 steel wool and 2 new 9 volts, survival matches, and wet fire tender. But I feel pretty confident that my butane lighter would be enough in most situations. They are virtually windproof.
On a side note. I have 2 pre-teen daughters. On every camping trip we take, at least once, I make them start a fire using nothing but their survival bags and stuff they can find on the ground. And in May or October at 9,000 feet, the stuff on the ground is not always easy to light. Now it's become a contest for them. They go out of their way to start a fire using wet kindling and wood that is not great just to prove they can.
At least I know if my kids ever need to, they will know numerous ways to start a fire.