Photographing people, there are some significant limitations and a few significant advantages.
I got these:
https://www.amazon.com/gp/product/B0119EO0MY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1I found this comparison between the Ice Light and the one I bought useful. You will see comparisons using a mannequin head later in the video which give you an idea of how powerful they are compared to each other and also the quality of light. The exposure data gives you an idea how much output you can expect.
Another comparison between the Ice Light and another, similar knock-off:
https://m.youtube.com/watch?v=ayDovpnDtmcThis video gives some insight into how one photographer uses these lights.
The good: you can see what you are getting, it is much quicker to use, even an untrained assistant can usually hold it correctly with little instruction and if they get it wrong, you will see from the light on the model (where your attention is) instead of when you look at the shot after. The quality of the light is good. Very easy to get the "high window" effect. Also easy to conceal in small places. It can actually be used for a little extra light outdoors in the shade, but it is subtle--improves the quality but it is not going to become the key light by any stretch
. The one I got runs off of standard, inexpensive Sony camcorder batteries and came with a tungsten adapter (plastic tube) and detachable barn doors.
Not so good: can be bright in the models eyes (there are ways to manage this--turn it on at lower power facing away, warn them its bright and then introduce it), does not provide much power compared to a flash.
The disadvantage list is short but should be carefully considered. Lower shutter speeds, larger apertures and higher ISO levels you wouldn't need with a strobe.
I find it useful but it isn't replacing a strobe
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There are some interesting LED units which aim to serve as monolights, some including Bowens mounts. These seem promising, some claiming to have power at the level if 1K tungsten lights and CRI numbers as high as 95 (good color). This is significant. It's still not at the level of strobes, but it's pretty usable and we don't always want or need the power of strobes.
Strobes give motion stopping and the ability to vary against ambient by shifting shutter speed and aperture separately.
LED and other continuous sources show you what you are going to get. This is especially helpful with carefully placed hard sources. Think of Hurrell's Hollywood portraits.