1. Which drivers to you suggest to most smoothly run booth an A1200P and an B400P in the same system, chanMISDN or Bristuff? Plan to use Asterisk 1.4.
i think mISDN+zaptel is better.
2. Is the D-channel supported on the B400P with either of the above drivers?
yes. it support 2B+D
3. Do you have example configurations for the B400P?
for B400P, you can refer our user manuals include for mISDN and bristuff. but we do not have a configuration file for A1200P+B400P. you have to study on it.