You can read about the Twinlight Driver on the link here
http://www.srwmoto.com.au/electrical-electronic/twinlight-driver-both-bulbs-on-all-the-time/prod_469.htmlI am offering an AU$25 discount until the end of November to ST.N members. The easiest way to get the offer is to PM me and I will send you a discount code that you can use for an on-line order.
This is my Firebolt on low beam now - the bike has 90 mm Hellas so it is a bit different to stock but shows the effect.

The main features are >20% more power to one bulb and >40% to two bulbs. On a Daytona with an H7 low and an H9 high this gives 44% more light output on low and 67% more on high. The manufacturer measures more forward focused light output with the Twinlight Driver running Philips +50% bulbs than with HID accessory bulbs running in a reflector designed for a Halogen bulb. There are animated images of the differences on the link.
These were specifically designed to suit Buell XBs, but they are fairly generic and are a simple fit with many bikes that run H3, H7, H9 and H11 bulbs.
That is without any of the other twinlight features enabled.
There are my settings. The ones I use are:
- Daytime and Low-light modes controlled by a light sensor.
- I have Daytime mode low beam set with high beam at 46% brightness and discrete modulation
- I have Low-light mode set to have the high on at 35% brightness with low beam (in the picture above, high is set to 43% brightness on low beam).
- Both bulbs on full with high beam
- If the low beam bulb fails high automatically comes on at ~50%
- Delayed headlight turn on after the ignition key is switched - saves on bulbs and batteries and makes the bike easier to start.
- I use a Philips +50% in the high beam to get the same colour effect as the low bulb when the high bulb is running dimmer.