Are on camera video lights useful?

[boxtree]

Starting to see quite a few on cam LED lights when I go to expos and festivals. Are these dslr hotshoe add-ons indispensable or a waste of money. Thoughts please? If you do you use them any tips or situations/scenarios you would recommend using them.

thank you 

[dbp]

I use the F&V r300 alot. Mostly for weddings, but sometimes for other fast paced stuff that's dark.

Works great, looks much better than most on camera lights I find. There's a diffusion panel that comes with it, and they sell a much more diffused one separately that I'm planning on getting. Partly for the look of the light, and partly because it's much easier for people to look at without going blind. It can get quite bright.

It was 300$ Canadian. For what it is, worth every penny. 

[The Chris]

I use one all the time for fill on faces during interviews. At expos and festivals the light is really uneven, on cam fill smooths things out and cuts the harsh shadows from mostly overhead lights, flattering your subject. It's also helps to separate your subject from the background a bit.  Something like this does a great job. 

http://www.amazon.com/YONGNUO-YN300-III-Temperatur-Adjustable/dp/B00RJSTJ6C