30ng of D3 is the lower end of the "normal range" currently used in medical testing in US. If you follow the new D information, 30 is too low to accomplish further benefits which only show up at higher serum levels.

Here is my D thread with a medical video explaining:
http://neurotalk.psychcentral.com/thread85103.html

It is up to you if you want to explore further D options.

MMA is another B12 test. It shows if you have enough B12 to metabolize MMA properly. It is a good test, but some people just need more than others. Without a serum test as well, you won't know where you are exactly.
Here is the link to Dr. Snow's medical article on B12.
http://neurotalk.psychcentral.com/post698522-70.html

He believes there is a small subset of people with fairly normal blood readings who still suffer from neurological symptoms. For those people he suggests using B12 anyway, since it is non-toxic and inexpensive.