Any of you King Air operators done any research on TAWS/EGPWS and DRVSM certification for the King Air B200? We operate a B200 (Part 91) and I need to start getting some facts and figures together on doing these on our aircraft. What companies offer these modifications; who to contact; pros and cons of one manaufacturer vs. another; approx costs, and "downtime"; etc. Anybody who has already been down this road, or is going down it now, I'd like to hear from you.