If you decide against LED can, my second preference in shower area is fluorescent. I know, I know..BUT there is twice the light output with fluorescent because it doesn't get as hot as incandescent. I used a can rated for up to 32 watts because you can go as low as 24 watt and as high as 32 watt. For the trim, a "regressed, frosted lense" will give you a nice, soft glow similar to a flood lamp, but I strongly recommend a good quality fluorescent lamp (Sylvania) at 3000 Kelvin. Juno is the only manufacturer that has a regressed trim that will work with a 32 watt.(32 watt lamp is longer than 24 watt so if you decide you are ok with 24 watt, there are more manufacturers available.) I've installed this configuration right next to a can with incandescent flood (in kitchen) and no one could tell the difference in both color and look between the fluorescent and the incandescent.

Here is my experiment trying to adapt a Philips/Lightolier Corepro cp630k10 to a standard Lightolier. This technique should also work with CREE CR6 and other systems that use friction springs/claws. Also, for the record, the light pictured here is feather-weight. For an adapter, I picked up a 6-to-5 inch HVAC reducer from Home Depot (~$7), as that seemed the quickest way to experiment. The logic is that standard Lightolier fixtures are expecting a 6-6.5 inch cylinder to grasp on the outside, and CorePro and CREE lights are expecting to grip a 6-6.5 inch cylinder from the inside. So, why not make a sleeve that fits around light? Shown below is a picture of what I've done. The end results (which I'm not showing ) are so-so: the light doesn't fit flush against the ceiling. That's probably because there are now two points of failure instead of one. Also, the cp630k10 has a slightly smaller diameter than the trim it replaces, which ends up revealing an ugly part of the ceiling that was never painted. It's definitely worth experimenting with. Ultimately the best method would probably be to either firmly attach the light to the sleeve (using glue or screws) OR to use a Juno or Halo remodeler. Both of those will have expanding clips that prevent the sleeve, er, remodeler can, from pulling down from the ceiling, but Lightolier uses larger than standard holes, and I'm not sure if their lips are wide enough to grip the ceiling from below. Of course, if Phillips/Lightolier would simply come out with an affordable light that fit their millions of installed fixtures, life would be much simpler.

Hmm, it's rated 575 lumens and uses 10.5 watts. That's about 55 lumens per watt. That's showing some improvement, but it's still well below a good CF in efficacy - and it's quite a bit more costly. By comparison, the low mercury 12,000 hour Neolite retrofit Edison base CFs I've mentioned here before yield 72 lumens per watt and cost $4.50 each. Compared to those, the Crees use 32% more electricity for a given amount of light, and cost 3.8 times as much per average life hour - and 11 times as much per lumen-hour. Ouch. On the downside, the Neolite CFs aren't dimmable. Also, if you're married to downlights, the Cree may make better use of its lumens since they're all aimed downward.

CREE lights can be used for new construction too. The LR6 can fit into title 24 cans (with the GU24 base). I would go with the HD CR6 if you can use edison base lights. If you're subject to title 24 like laws, you need to use the GU24 base which is currently not available from HD. The other resellers (polar-ray) of CREE CR6 lights have a higher list price ($65), but the warranty period is longer.