Regardless of which type of lighting one eventually chooses, you need to consider factors such as running costs (power, bulb replacement, cooling), controlability and expected life of the fixture. Budget may play a role, but, in most cases we are talking about an important piece of equipment that should have a lifespan and flexibility fitting our needs for the projected time period. Personally, I want to get about 10 years use out of a fixture, if I'm going to invest in it. For the stability of my reef, a cheap, uncontrollable and less than reliable fixture is simply not an option. I have corals and fish with a worth many times more than the most expensive fixtures on the market and want to keep them. Along with the filtering system, lighting is an area not to be skimped on. You only end up paying for the mistake, often in less than a year. You know the adage; a cheap tool is an expensive tool.
I have been using LEDs for over 18 months (Vertex Illumina SR260) and would never go back to halides and certainly not T5s (hate the flat, candy-coloured look. The corals look like plastic!). For myself, LEDs are clearly the lighting of the future. Colour developement is excellent, growth rates are strong (for me stronger than halide/T5 combis) and the controlability is superb. Something that has become clear to me over the last 18 months is the effect of a more natural light cycle. We are not just talking spectrum, which does change continuously over a natural reef, but the subtle changes in intensity and light angle that are found in nature. With previous lighting options, attaining control on the is level was simply impossible. A good LED setup allows a much better control and the tank responds to this. With my lighting i can control the colur mix throughout the day, vary the intensity and colour mix over the entire length of the lamp, 'walking' the changes across the pads, thus creating a much more natural lighting scheme. The same for the moonlight. This fine level of control is slowly noted in the developement and activities seen in my reef. Fish notice these changes and synchronise their activities to the changing light patterns. Many animals take their spawning trigger from the light, as well.
In the end, with a good LED fixture, you can create any kind of lighting effect you wish, except one without crinkle effect, but who wants that? (certainly someone, but taste does lie on the tongue) By choosing the right fixture, you can have a completely up-datable piece of equipment that will serve you for many years and allowing you to customise your lighting as you develope through this hobby.
just some thoughts,
Jamie