10w is fine to see by, but not to work by. I have a dead 10w on the shed for getting to it at night (which this will replace) and a 30w on a switch for if I need to work outside at night. I also have a 50w but its brighter than I need so it's still in its box!

Very vaguely LED lights are about 10x more efficient than standard lights, so think of this as a 100w traditional floodlight.

​that would apply to any light, if you have a traditional floodlight the cable comes away from the wall to go into the light , so plenty to play with.