So, Black Friday finally pushed me over the edge, I'm making the switch to LED's. I have a DIY 24x3w cree fixture in the sump (thanks, sfork!), and I'm pretty happy with it. Yes there's some color banding, but it's never really bothered me. A wide variety of coral colors look good under it, it's simple enough that I've rewired it myself a couple different times, and it's put up with quite a few "oops" situations. With the new XM-L emitters out, I think the technology should be able to do the job on the display. I've looked at tons of different options, and eventually settled on the maxspect mazarra p-series, with a few reservations due to the complaints on the other reefing forums. The flexible mounting system, and the interchangeability of the emitters and lenses is exactly what I've been looking for from a new lighting system. I've just pulled one of the lights out of the box and tinkered with it a bit, so here's some photos and notes [particularly, answers to the questions I had a hard time getting answered prior to purchase.] So far I'm pretty optimistic. To replace emitters/lenses, there are four thumb screws on the bottom of the unit. Just unscrew and use a small screwdriver to gently pull off the cover: The entire housing as far as I can tell is plastic, just the heatsink is metal. The lenses just pop in and out of the housing, there were no o-rings in this unit. If they feel a bit loose in the panel at first, it just means they need to be snapped in further. The routing of some of these wires is a bit goofy, but anyone who knows how to use a screwdriver can switch out emitters to suit their tastes. The power cable for the fan hides well enough. Their documentation says that their "passive cooling system" is sufficient to keep the LED's from overheating, but I know how hot the heatsink in the sump gets when a fan dies, so I'm skeptical. This little "cart" is where the ball joint screws onto the fixture, and it slides along that silver rail, so the light has quite a few degrees of freedom to be aimed to one side or another of the mounting rail. This is the ball joint, and it's solid aluminum and feels pretty sturdy. This is the part I was most worried about when ordering. In my experiments so far, the ball joint is a bit fussy, but if the set screw goes in tightly enough, it's reliable. The whole mounting rail system is extruded aluminum, but I think they went too far with the "modular design" of the rails and should have just opted to sell rails in different lengths rather than dealing with all the screws/extra parts required to connect multiple short lengths of rail. There are four different channels on each unit, one at 1500ma (for the XM-L's), two at 1000ma, and one at 700ma. They can be turned up/down in 1% increments via the units themselves. If you don't want any weather/dawn/dusk effects, there's no need for a controller. The backlight in the LCD panel goes off after a few seconds of inactivity. Light!