DDM is hit or miss. Though since they're local to me, I thought to give them a shot for my Civic. $30 for a set, why not. It's been a year now and so far they're still fine.
Anyways, back in my forum, these are the popular non-DDM choice:
http://www.kbcarstuff.com/HID-Kits-s/216.htm
Hear good things about them and the Volt look good for the money.
And they stand behind their products.