I guess I was lucky to come into the hobby 4 years ago when LEDs were catching on. My first fixture that came with the used tank I bought was an underpowered T5. I came across someone selling their AI Sol's to switch back to MH, so I got them for 1/2 price. Over the. Next 6 months as my tank matured, I added SPS frags from him, and other MH reefs. As I went back and visited my friends with the mother colonies, I noticed 2 things. #1 some of the colors on my corals changed, but some were better and some were not as good. #2 my growth was just as good or better. So after 3 years of running the Sol's I have to say that anyone who says they dont get as good of growth under LEDs is doing something wrong. Then I upgraded the Sol's to regular Hydras (not the 52's) and 1 Vega. I lowered the overall brightness and have taken 3 months to raise all the channels to be equal, and get the same overall brightness as my Sol's. I have seen lots of color changes again in my reef, but again the growth is spectacular.
I have never run halides so I cant speak for my experience with them, but in comparison to other tanks I get just as good results. The price I spent on the full spectrum upgrades and new controller have wiped away any savings from bulb changes. When I think about the difference in electricity costs, maybe I am ahead, or maybe Im behind...who knows...but Im not in this hobby to save money, its a losing adventure except its a small price to pay for how much enjoyment I get my reef.
I guess my point is that people will probably have the best luck with whatever equipment keeps them interested in maintaining their tanks and good husbandry. As long as they have adequate light from whatever fixture they own, their corals will grow and be beautiful.