headlight wiring harness

I'm currently upgrading the lighting on my mk2 mr2 and was wondering whether its worth doing the headlight wiring harness upgrade. After looking around on the net i've found that there can be some voltage drop between the battery / alternator and the actual bulb. Here is an example of what i've read :

In many cases, the thin factory wires are inadequate even for the stock headlamp equipment. Headlamp bulb light output is severely compromised with decreased voltage. The drop in light output is not linear, it is exponential with the power 3.4. For example, let's consider a 9006 low beam bulb rated 1000 lumens at 12.8 Volts and plug in different voltages:

I've just checked my cars voltage and the battery is at 14.5 but the power to the bulbs is 13.7. Do you think its worth upgrading the headlight harness or will it make very little difference to my car?

After working out that i'm having about a 5% voltage drop and going by the above figures then i'm probably only getting about 80% light output from the bulbs. I would imagine that this would be a noticeable difference.