The other thing that folks need to remember is that to use the 800 twin, you still need to monitor both capsules. The only difference is that you don't get locked into a pattern in a multitrack situation.

Front and back in phase and equal gain makes an omni. Just the front will be cardiod. Flip phase on the back with equal gain and you have fig-8. Lower the gain and you have a hypercardiod.

Like any recording, you still need to have an idea of what kind of a sound you're looking for and how you want to approach it.

-Ben