It's only 10W, that's not really much as a main light source at night.
I've been working once with the HVL-20 from Sony (the dual-head 10+10W on camera light). It was a real pain, it throws the worst beam you can imagine, you could just as well use a Maglite. It would be perfect to imitate a flashlight if you're going for that look. I put some 1/4 or 1/2 WD before it to make the beam acceptable, but then the output was nearly enough as a little fill even with both lights on. I didn't even bother to use one of the 10W lights alone.
Take a look at the TL-50 by Switronix/Torchled...great light output and just under $300. The price is well worth it since the quality will outlast that sima junk. The TL-50 Has an internal battery that lasts me just above 3 hours and no crappy plastic housing like the others mentioned. You can buy it on Amazon too. Heres some links to help your dilemma