Just used the travel tray on a recent trip to Panama. It really made going through the TSA security checkpoint a breeze. Not sure if I read about it here or in another forum but what I did was put my 311 liquids in a quart ziplock bag and put that in the travel tray and the travel tray in my bag. When I got to the security checkpoint I took the tray out of the bag and the quart ziplock with my liquids out of the tray. I then put my watch, phone, etc (basically everything in my pockets into the travel tray, zipped it up, and threw that in the bag. This way all my stuff was not out in the open for anybody to pilfer. After going through security I took everything out of the tray and put the quart ziplock back in. It really made going through security a nice tidy affair.
I always have some kind of tray when I travel to put loose items like my phone, glasses, keys, coins etc so they are handy and don't get lost. I was using one of those flat trays where the corners snap together and while they work good for a few items I found the travel tray much better because it has a greater capacity, plus it serves as a dual use item for going through security as described above.
This is a handy little item that you really don't need but it really is extremely handy. I'll definitely be using this on all future trips.