I just put my LED fixture for my 120 gallon together this weekend. I'll post pics later as it is still a mess of wires. I've still got a lot of cleanup and organizing to do. Gluing, soldering, wiring, etc. wasn't hard, but got a bit tedious. It took about three hours to solder the wires to the stars. Don't let the soldering scare you away. I used Solder-It compound (from Lowes, in the plumbing section). Just put a dab on the contact, push your wire end into the dab then apply the tip of the soldering iron (30 watt iron). The contact grabs the solder when it melts and the solder won't stick to surrounding area on the star, so it automatically goes where you want it. It was definitely easier to get the soldering right than I had feared. You just take a toothbrush and brush away the extra compound when you are done. I did an ugly job on a few of the contacts. I just remelted the solder, added a bit more compound, and repositioned the wire-- no problem.
The fixture is a 72" x 4.25" aluminum heat sink with three groups of 28 XRE LEDs in two rows, 50/50 white/royal blue. I really like the color, and it seems plenty bright. I've got a 4xT5HO fixture on my 30 gallon and the LEDs seem brighter. The blue is really very blue. I don't think it would need more blue, but everyone's perception of colors is different, so to each their own.
I'm using the 70 degree optics, which really boost the amount of light hitting the prime coral growth area. I don't have a PAR meter, so I don't have a specific measurement, but the difference with and without is very noticeable. If you use the 70 degree optics, you won't get much light in the upper water column along the tank sides, but my rock runs as a ridge down the center, so that works for me. I like the look. It isn't a "spotlight" effect, but it does highlight the ridge down the center.
I went with fewer LEDs to start than I had originally planned since I've heard many people end up dialing their power way back when they load up with lots of emitters. I've got room on my heat sink to add another row of LEDs, so if I find I don't have enough power, I can always add more. The power supplies I'm using (Meanwell ELN60-24D) will run the LEDs at a max of 800 mA (4 supplies, three parallel sets of 7 LEDs on each supply). I've got an Apex to manage sunrise/sunset, but haven't hooked it up yet. I'm just using a Walmart power supply that puts out different voltages (3v-12v) to control the dimming now for testing.
All in, I'm just under $1000 for the fixture, including fans, wire, connectors, etc.