I have 2 lights, so it does not look odd with only one light on one spreader.
If you can get two, it helps at night when you need to work on stuff. And I had to use them on several occasions.
Unfortunately I got these swivel light
from West Marine , and their construction is very bad, they filled with water and failed. Water enters thru the hole in the swivel. I brought them with me and West Marine gave me new ones for free of a different model that is built in such way water can't get in. The new ones are not swivel, but also don't have the hole for water to get in.