I have the same setup, we airplay to the ATV3s on our TVs with stuff from the PC/Mac via a server software that will encode ANYTHING you throw at it, with no lag whatsoever, 720p, 1080p.
I've wasted money on others that dont work as well , this one i highly recommend.
Any chance you have an iPhone or iPad? Collect3 has an app that lets you stream video from your pc or Mac to your IOS device.
Also, traveling with videos on your laptop shouldn't be a problem with TSA. If you're trying to take stuff that's illegal, the problem is the videos, not TSA. :)
If it's legal and just something you don't want anyone to know about, add a TrueCrypt file container to the machine and put the videos in there.