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 the room and over 60 degrees avoids pools of light. So between 60 and 100 degrees works best for general use.
Make: There are hundreds of manufacturers from the top to the bottom of the market and price is generally an indication of quality.