DHA is important for the structure in the brain. It is the main fatty acid for pregnant and nursing women. (for the growth of the brain of the child).

I am not sure that it is so essential for the nerves already there however, in the periphery. I searched a bit and found only
central recommendations so far:
http://www.springerlink.com/content/e50146hq40251400/
you'll have to zoom to read it.

All the suggestions I am finding say, central gray matter stuff.

But you know, it is up to you. NatureMade is sold at Costco, but I don't recall if they have the Fish oil (they sell their own brand for that) . Also KMart has it...so when they have buy one get one free, you can save alot of money. Which ever outlet you choose, join on their website for points. For that big Fish oil you should get about 100 pts or so.
At the 500 mark they send you a $7 coupon. There is an 8 digit code on each bottle. Don't throw it away before writing it down.
I've saved a bundle this way. I got a full year's supply of their Flax oil, buy one get one free at Kmart and used the $7 coupon besides! all for $7.98! They have a great customer phone service, which I have used at times for information.

This is not a big issue for you. If you were pregnant, you would want more DHA...however. Regular fish oil should work for you.
It is less costly than OmegaBrite anyway. The company OmegaBrite is owned by Dr. Stoll's wife, and he has a book out about his studies with high EPA fish oil and Bipolar treatment and psychiatry in general. He used this product in his studies.