I have been using the Spectrum Lighting bulbs (250w MH 14k and 20k) for about 4 years now...something like that. They have worked and who can complain when they are so cheap. But, I have found that the bulbs should be replaced about every 6-8 months to keep their color and to keep the corals growing fast. I also noticed that after about 6-8months algae creeps in. Just based on my experience with them. I have also experienced bad bulbs on and off over the last 4 years...they will flicker or not output the same spectrums from one bulb to the next. Lack of consitency.

I recently had store credit to burn so opted to try some reef brand bnulbs again. XM has always been my fave. I picked up 2 250w 20k mh XM bulbs and have already noticed a faster growth rate on my corals and the color is much better IMO than the spectrum bulbs. Yes, the spectrum lighting kept my corals growing and the colors looked nice BUT I had to replace the bulbs more often and honestly I'm finding better growth rate and better colors with the XM bulbs. I would guess the same would be found with any of the other reputable brands.

Guess it just matters what works best for you. I personally will only use reef brand bulbs on my display tanks moving forward and the spectrum lighting bulbs will be used for any frag tanks I keep.