Very interesting Owen, it's always a pleasure to read your lighting posts.
I didn't know about this "Falcon Eyes" light and wonder who actually makes it - Falcon Eyes, like Neewer, just buys up products from factories and re-brands them. What's the diameter of the actual Fresnel lens?
Size matters here. Back in the 80's and early 90's I used fresnel spots quite a lot, sadly I've never worked in the movie industry but I did the lighting for a lot of TV commercials and fresnels were very useful because of the dramatic light quality. We used to hire them in for each shoot and were all made by Arri. They were pretty massive and so very versatile. They were slow to use, mainly because the lighting in TV adds has to be perfect (it used to cost £1000 per second of screen time on LWT back then) and usually took 2 days to shoot a 15 sec commercial, so it didn't matter.
I later used a Bron one, which was an attachment, for still photography. This had a diameter of 14" and was a beast, but very useful. It's still in Malaysia somewhere, long story that I won't bore you with. Back in England I bought another Bron one, which had a built in flash head but unfortunately the generator blew up and I never got around to replacing it.
Later still, I had a meeting with a large studio lighting manufacturer in China. I was the foreigner who couldn't even speak Mandarin and although they were scrupulously polite they obviously didn't want me there. They had a series of excellent portraits on their boardroom wall and, bored stiff, I said that the lighting on all of them was superb and I was especially impressed with the one that was lit with a fresnel spot - that changed everything, their chairman was a keen amateur photographer who actually understood lighting and we had a long and slow conversation via the translator and suddenly I was accepted by them. After that, I became the only photographer who they listened too and I think it's a great pity that the big Chinese manufacturers of today are only interested in making money and know and care nothing about photography.
It turned out that they made a fresnel spot attachment, it was so specialised that it wasn't even in their catalogue but we bought it and it was sold by Lencarta for several years. Mechanically it wasn't great, but it had a 8" diameter lens and did a good job. Other firms then introduced their own versions, the best one that I tried was made by Bowens but, at just one inch smaller, was nowhere near as good.
I've never used a LED one and can't help wondering whether the LED array is small enough to work well - the old tungsten ones were perfect, the flash ones less so because the flash tubes were too big, and with flash there's also a problem caused by the modelling lamp being in a different place to the flash tube.