I use this Q5 light from Shiningbeam in addition to my MTE 8 mode P7:
http://www.shiningbeam.com/servlet/t...50-Cree/Detail

The MTE is bar mounted. The other light is a thrower and is helmet mounted. This gives me significantly improved visibility over just the MTE P7. I rode home through Toronto's pitch dark Don Valley trails yesterday, and had no visibility problems.