Haha.... oh, KCs.
To me, KC is the epitome of a company that creates a product for form... not function. Chrome bling... free form reflector... smilie face covers... and a beam that is made for an aircraft. KCs are for people that want a light that looks retro... that's about it.
They were created back in the hay-day of off-roading. You'll see them on a ton of jeeps back then... but they weren't used. They were there because that was 'the thing'. KCs have a great following by people that just want some lights on their roof. Yes they're almost an icon... but it's just because they were popular a long time ago and had a market share back then.
There have been so many improvements to lights since the classic KCs came along. Plastic housings reduce weight (which reduces vibrations), faceted computer generated reflectors spread the beam out into useful patterns, glass ribbing spreads the light horizontally and keeps glare down...
Then there's the beam pattern. Long and narrow beams are not desirable for off road... unless you're going to be predominately traveling at high speeds when you need the extra lighting... in which case you do want a long and narrow beam. But even then... you want a driving light, not a pencil beam.
A good off road beam is a wide low pattern. I recommend a fog or "cornering" beam for your main driving lights. I'm very happy with my Hella Micro DE and my Hella 4000 Cornering lights. The Hella 550s are ok, but even they don't throw the light down exactly where I want it... I'll try to get a comparison shot for you in the pitch dark during TECORE.
Plus, the KCs are just soooo retro!
Anyways, here's a 3rd party review of lights. The iconic KC day-lighters received a poor rating:
http://jd.offroadtb.com/light_comparison.pdf Note, this was an Australian review, so most of the lights cannot be found in the US.
If you want more feedback... just look at what brands were used by some of the past iconic expedition events... like the Camel Trophy. You'll basically only see wide angle Hella products on those vehicles. Hella = expedition, KC = mall. Thats just the way I see it. But don't just listen to me... find your own reasons.

