That is partially good news - just remember that LED down(spotlamps)lights shine their light in small pools determined by the beam angle.
Use this to see the difference between say a 38degree and a normal pendent light.
http://www.lightbulbs-direct.com/article/spotlight-beam-angles/
If you look at the pools of light produced by downlights you can clearly see that you are going to need a lot more to provide the same amount of light as a standard pendant - probably in the region of 6 - 1.
Having dark areas is okay for ambiance but not okay for a kitchen where you are cutting things with sharp knives. In my view in the kitchen it is better to have a good quality central light backed up by undercupboard lighs in areas where you work
Also don't forget that LED downlights are less powerful than halogen with a 5w giving out about the equivalent lumens to a 40w halogen.
You will need to get something in excess of 5w to meet the standard 50w halogen lumens standard.
Finally, expect to pay between £35/40 for a good quality LED unit. Ignore the adverts that say they produce little heat - look at the size of the heatsinks on them.
If you put them in an upstairs bathroom then you will need to keep them clear of loft insulation.
