I use anywhere from about 20 lumens to 130. Just depends on the situation, as others have mentioned. Think about what you will be doing on a daily basis, and how much light those tasks need. If you are just finding your door key standing at your house door, 20 lumens will be fine. If you are looking for a lost dog in the woods, well as much as you are willing to afford.
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Keep in mind battery costs as well. Rechargeables are great, as long as you are willing to maintain them. Some people prefer to just use consumables or at least have the option. Will you often be needing the light for many hours/days straight without access to AC power for a recharge? Or do you intend to come home every night and be able to check the batteries? Most rechargeables in most situations won't need checking every day, unless you are replacing headlights in your car in Alaska.