Driving light?

I posted this in lighting but got no responses. I am getting a Nfab 4 tab bar and have decided to mount KC 6" long range 130 watt slimlites on the outside. On the inside I will mount driving lights but I am having a tough time deciding on 5" 55 watt or 6" 100 watt. I really like the look of the smaller lights in the middle but my main purpose here is illumination. I am just not sure how much I will gain from having the 6" versus the 5". I was thinking that I could go ahead and get the 5" and if they are not doing the job maybe put a 100 watt buld in them or put them on my ATV.

 

hate to poop on this thread but if illumination is your goal
skip the KC's and get better driving lights

spot beam
fog beam

Cibie Oscars, accept no subsitutes. These are engineered to perform.
No one can beat Cibie reflector design, it is the ultimate in incandescent driving light.

http://www.ebay.com/sch/i.html?_kw=Cibie+Oscar+Driving+Lights

http://www.ozautoelectrics.com/automotive-lighting/driving-lights/cibie-driving-lights.html

http://www.danielsternlighting.com/products/products.html



for the KC question 5 inch vs 6, there is a good difference with the extra inch,
more than what it would seem on paper.