My existing cabin lights were in need of being replaced.  They were a mixed match of various manufacturers, mostly halogen, and very good at sucking a lot of power.  A couple were older flourescent lights that didn't work at all.  All of the halogen lights got too hot to touch in about 5 minutes, and while they provided a lot of light, they were mostly reading or spot lights, so the remainder of the cabin was relatively dark. 
I wanted to use both LED and flourescent lights in my new design for power saving purposes, and I wanted the majority of them to be able to switch from normal cabin lighting mode to night vision mode.  I ended up with three different types of lights based on needs:

• Adjustable LED light with both white and red color for reading/nav area
• LED Reading light for reading area
• Flourescent and LED light combo for everywhere else

When selecting my lights, I did a lot of research on manufacturers, power usage, and features.  At the time, it seemed like the LED light craze hadn't completely been embraced by all of the major manufacturers, and that limited some of my choices.
I chose the Resolux 505 Elegance LED light from Imtra Marine Products as my all purpose light.  I have three of them in the main cabin – one near the galley area, one near the nav station, and one in the center of the main cabin over the table.  These lights have very efficient flourescent bulbs that provide a large amount of illumination, and a set of 6 red LED's that can be used for night vision.
Install was simple and straightforward – one nice feature is that the electrical connections are blade connectors, not raw wires, which makes for a cleaner connection. There's plenty of space behind the light for routing wires, and drilling holes in ends or sides is possible with the space as well.  The light performs very well, and provides a lot of good light in both modes.  The only issue is that the red LED lights are mounted on one side of the cavity inside the light, so most of the red light will be projected to one side of the light.  I ended up having to reverse the light so that the red light shone where I wanted it.
For my reading light, I chose the Sydney LED light, again from Imtra Marine Products. I have one of these near a common place for reading, and it provides plenty of natural-looking (not quite natural!) light for reading or other projects.  The light itself is well made, but I had a couple of issues with it.  First, the space behind it for wire routing is non-existent.  It was very difficult to route wires, and work behind the unit.  Second, the light gets pretty hot after a few minutes, although nowhere near as hot as the old halogens. 
Overall the Sydney LED light draws a tiny amount of power for the light it produces.  It allows you to swivel it pretty much anywhere, and it looks good too.
The final light I installed was a flexible reading/chart light, again from Imtra, model F4 TouchLED.  This light didn't have any switches, and automatically turns on the red LEDs when it's dark out.  The auto-on functionality is nice when entering the cabin from outside so you don't have to fumble around.  The touch on/off is convenient too, although a bit annoying when you brush up against it.  The only complaint about this particular light is the wiring – very little space behind it again, and also very small wires.
This upgrade was extremely beneficial to both the safety and the electrical system on the boat.  The amount of power used is a fraction of what it used to be, which means less draw on my batteries, and less problems overall.  Not having the heat associated with the old (and dangerous) halogens means that there's less chance of a fire or other bad electrical issue.