by John Chatterton via: (http://www.johnchatterton.com/dive-locker/primary-light/)
I remember a day when my old Darrell Allan light was the wreck diving standard. It was not bright at all, but you could also use it as a hammer. It was a big can thatused like 10 alkyline batteries, and sometimes the bulb would fall out of the socket in the middle of a dive. It was the Prince of Darkness. That was then, and this is now!!!!!
Modern lights are specifically designed for different uses. I do not use the same light for everything, and I often carry more than one, but my Primary Light is going to have to be the best all around light for the diving I am doing. It has to be rugged, have decent burn time, and it needs to be bright.
My favorite Primary light is the new Sola Tech 600 by Light and Motion. It is bright, but with lots of brightness options, and plenty of burn time, depending on the brightness selections. It has a very cool hand mount harness that means I can use both my hands while using my light, so.I can easily use a reel with this handle, amongst other things. It also means I point the light intuitively with my hand. The rechargable light comes with a smart charger, and an operating manual, which takes like 2 minutes to read. It is very intuitive, capable, reliable, and rugged. It is lots of light, in a surprisingly compact package.
There are several Sola models, but for me, the Tech 600 is the best balance of Burn Time vs.Brightness..I predict this is a design that will be copied by a lot of other manufacturers. I love the Sola.
I wonder where my old Darrell Allan light is these days???