yeah i dont know much about the old ones. i just have seen what my LFS carries. everytime i go in there's swarms of reefers huddled around the display tank that's using these fixtures. id love to try one on my planted tank but the initial investment is a little too high. they really are some impressive fixtures. they even run them on the big frag tanks and freshwater planted tanks.
they said theyre trying to switch all their tanks over to these fixtures. they estimate the cost saving in electricity could save them over $3k a month since they have hundreds of tanks in this shop, not to mention the massive MH fixtures on their reef tanks