Roy:

Fluorescent lights are a more efficient technology than
incandescents (about four times the light output of an
incandescent for the same wattage. In other words, you can
get the same light output for one fourth the wattage.  Very
nice, indeed, when you are drawing power from your battery.
A fluorescent lamp has greater longevity as well.

I assume the light you are looking at is a 12 volt lamp.
The color of the light emitted from fluorescence has
generally been in the blue color range, which is
disconcerting to some peoples eyes.  Many of the newer
compact fluorescence have a warmer (i.e., red coloration)
and give a very nice color rendition.

Fluorescence do not have a filament like an incandescent, so
they aren't as susceptible to damage from vibration or
impact.  A fluorescent does operate with a "ballast" that if
magnetic can create an audible buzzing sound. Newer
electronic ballast fluorescence do not buzz.

Take a look at the wattage on the light you're interested
in. If it is above 12 watts it may be too bright for your
conditions. (I have a 12W fluorescent outdoor light above my
garage door and it easily lights all of the driveway.)  I'm
sure you'll do a test run before you install the lamp
permanently, right?

Well, hope this general discussion is of assistance.

- - George Chapman, 91 GL
    Lake Almanor, CA