I can only echo the advice about sucking up as much information as possible on your unit visit.
One caveat, however: When you get to your interview, don't be tempted to throw in a mention of something unless you are prepared to be asked about it. Most interviewers will just keep on throwing you a longer spade as you keep digging. This is not an attempt to trip you up, just to see how deep your knowledge goes.
So I wouldn't mention the NOTA, iFACTS, SES, FBA, Mode S or whatever unless you know more than the headline.
Good luck!