There's a danger of too much generalisation. The question is about continuous LEDs vs flash, but they can't be so broadly categorised - there are plenty of both rubbish/unsuitable and good products on both sides, and there's certainly more to come from LED technology.
But at the risk of offending the old school, Keiran's succesful business is about much more than LED vs flash. An experienced professional photographer will deliver the goods pretty much regardless of the equipment to hand, but what Kieran seems to have is a business model that produces good quality, quickly, easily and affordably. It's driven by today's customer needs and maybe there's a lesson to be burned there, if you'll excuse the malopropism.
Edit: and BTW, welcome to TP Kieran
With respect, his business model doesn't seem to be about good quality at all - judging from his website examples - but about high volume, fixed priced, consistent results that meet the expectations of his customers. There's nothing wrong with that as a business model and I sincerely hope that he does well.
Yes, there are good LED units out there, but very pricey and Keiran has gone in the opposite direction.
Yes, there are poor quality flash units out there too, but generally speaking, modern flash units are good and the old junk is now fading away.
Photography is a tiny business sector and there are no large companies involved in it, but basically it still follows the micro economic principles of all other businesses.
Businesses can be:
1. High volume low quality with low profit margins but high profits achieved via high volume and high market share, or they can go the other route with
2. Top quality products, first class customer service, very high profit margins but relatively low profits due to low volume.
3. Middle of the road, average quality, average prices, average volume.
No, forget 3, that used to work up to a point but it's now a recipe for disaster, very few people are now willing to pay more money for something that is only a little bit better.
No. 1 seems to the Keiran's route, and there's nothing wrong with that. It's a good business model, driven by internet sales (and especially by Amazon) and it has several distinct advantages:
a. It's infinitely scaleable. If sales go through the roof just recruit some more people, give them a minimum of on the job training, give them a well-designed system to work to, grow the business, repeat as necessary.
b. Improved cash flow, which can be used for expansion finance as necessary.
c. Economy of scale
d. Very low capital investment - or at least very low relative to unit cost - for example a machine that works 24 hours a day doesn't cost any more to buy than one that only gets used for 2 hours a month.
No. 2 is the skilled artisan route, e.g. a skilled mechanic who can make and mend instead of just fitting new parts or advertising photographer who can create stunning images of whatever is needed. It usually results in a very good living for a very small number of people, the limitation being that it's very hard to recruit highly skilled people and it takes years to train them, there's little or no room for growth.
There's plenty of room for both types of business model and I personally welcome both. The only problem that I have is when people who operate business type one masquerade as business type 2 . . .
Coming back to the question about LED lights, we know what the capability will be in a few years time, we know that the future is already here - it just isn't available yet at affordable prices - but in my opinion although LED lights can and no doubt will get better, the trend at the moment is for them to get worse.
Until a few years ago there were a lot of flash manufacturers in China, all doing OK, with their products sold mainly within China. Godox has changed that and now dominates both the internal and external market. Some of these smaller manufacturers have disappeared, some have switched to manufacturing non-photographic goods and others have dropped flash and turned their attention to LED, focusing on making them down to a price rather than up to a quality standard. This will change when Godox has saturated the flash market and concentrates on the LED market but the situation right now is that there are very few affordable LED lights that are suitable for any kind of still photography. They're fine for video but video is a small market, so naturally the sellers are promoting their products to the much larger still photography market, but the false marketing and b******t doesn't alter the fact that LED lights are a very poor substitute for flash and, right now, should be disregarded.
I've given LED lights a very thorough test, and at one point I did feel that they were good enough for serious use - but that was with a light that was pretty good compared to what is currently all over Amazon. However, as I did more and more testing I realised that even with a very high, genuine CRI rating, they still weren't good enough.