Choosing an LED Replacement Downlight
Some hints are:
Wattage: Divide the existing Wattage by nine to get the same brightness
Cut Out Size: Matching the existing cut out is ideal, but plaster or metal fillers are available
Colour: Warm White (3000K) is slightly whiter than halogen or incandescent bulbs but is usual for domestic use. Cool White (4000K) is used in offices and shops.
Beam Angle: Beam angles over about 100 degrees tend to catch your eye across and over about 60 degrees avoids pools of light.
Make: There are hundreds of manufacturers from the top to the bottom of the market and price is generally a good indication of quality. If you go too down market you will need to consider what to do with the holes in your ceiling if the lights fail.