Homeowner needs advice re: replacing existing hardwired under cabinet lighting
Replacing a fixture is, in my experience, not overly difficult.
I have LED undercabinet lighting and am very happy with it. Unfortunately, I have found that light quality and quantity can vary greatly. Shop carefully, though, and I think you can find something you are happy with. While I don't currently see big energy savings with LED over flourescent at this point, LED can offer some benefits in compactness of design.