Lets hope this thread doesn't follow the usual path . . . I won't even mention it!!
I find them very useful for myself . . . however, lights I leave out for family/friend access drive non-enthusiasts nuts when they're multi-mode. I've even seen some people struggle with the simple Surefire tailcap twist (like on the L1 and A2) their first time handling one so imagine handing them an Eagletac or mulit-mode Fenix!
For example, beacon mode can be used to find your car at night in a big parking lot (obviously you leave the flashlight inside the vehicle).
Strobe can very effectively signal someone in daylight in a sports stadium or across a soccer field.
Low level is perfect for blackouts.
Ideally there would be a button to press for each mode because cycling through all the modes you don't want at the moment will make you crazy. (Trust me.)
Gimme modes too. Being able to adjust the light to the task to preserve battery life is a big deal to me. The more the better unless more modes causes efficiency to suffer. Right now, my 3 favorite lights are the Titan T1A, U2A and the HDS Clicky.
It depends on what you use your flashlight for and if you're able to carry more than one light. Ever had to read a map with a 250lumen thrower ? It's ok if you can bounce the beam off a ceiling otherwise it's a pita. Most people only carry one light so they need it to perform in a variety of conditions. That's when one mode comes in useful. Even if you carry a backup, it needs to do the same function as your main. For example, if your primary light is a thrower, then if it fails a key-chain light probably won't be an ideal backup. That's why I love my HDS Clicky 170 Cn. It performs in a variety of situation. My backup is the HDS High CRI. It complements the 170Cn very well.
Multi-modes are my choice. For instance my night stand light is a HDS clicky. It's set to lowest level for checking on the kids and bathroom runs at night. However I just used it on a mid level to fix the bed and I use the mid level each morning to grab my work clothes. When I use it outside I use the highest level.
I have a Malkoff MD2 without the hi-lo ring. I need to buy one as that single mode is really too bright inside for me but great outside.
I like multiple modes... as has been said, you can read with a thrower, but only if it's in a low mode... or you cover it with a hanky or something lol.
My EDC must have multi... if I'm going to be using it for only half an hour or so, I'll use it on high for maximum brightness, but if I'm going to be stuck in the dark for longer, I need a medium or low (I don't tend to carry a spare battery and would rather not fall back on my tiny keyring backup backup).
I prefer 3 mode lights,a good low for evening use,a good medium for most tasks and a really bright high for when the need exists.I have no real use for any other modes but that does not put me off buying as one day I may find a use.
Big +1. I use single mode for weapon mounted and EDC defense lights and multi-mode for everything else. Most of my lights are 500+ lumens. If I didn't have multi-modes on them I'd be blinding myself and anyone nearby. The huge lumens is nice to have when I want the area clearly lit.
I find every situation where I need a flashlight to be different. Ones where I don't need maximum light, the lower modes are great for many reasons including lack of glare, protecting night vision and conserving battery life.
No single mode lights for me because I would have to carry 2 or 3 lights.
I was thinking of getting the MD2 but ordered the Elzetta with the Hi/Lo switch......It's built like a tank, takes Malkoff drop-ins, made in US, has momentary, 2 stage, and it's cheaper than a MD2. High is 235Lumens and lo is around 15lumens IIRC.
They make single speed bikes and multi-speed bikes. Most cars come with a fully variable accelerator pedal.
I was happy to have a light with just one level, until I got my hands on one which was capable of offering high output, but able to be run very low as well. There is no mistaking the favorable response to the variability of the Clicky and the 007, and for very good reason.
It's the other way round for me. Where's the "fun" in having to carry or switch to another light just because its too darn bright(or weak) for the purpose that you need it for.
I have single mode (~20-30 lumens) lights all over the place in my apartment.
But my current EDC is a 3 mode Quark MiNi AA WARMS.
Low 2 lumens good for close in work like reading menus in dark restaurants.
Medium 18 lumens good for general use indoors.
High 65 lumens a bit more light for outdoors.
Thank god the blink blink modes are hidden.
Unfortunately the most used medium mode is the 2nd mode.
That is why I have single mode (~20-30 lumens) lights all over the place in my apartment.
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Actually many of todays lights from 200 to 600 lumens or higher are too bright for close in work so a lower mode is required.
The lowly 65 lumens high of my Quark or even the 18 lumens medium is too much to read a menu in a dark restaurant. Too much back glare.