I use them both - here are some points.
The Travel Vault (made by Pelican) and the Starlight look very similar, but they aren't. The TV is somewhat heavier, provides great sealing from moisture and dust and shares a roughly similar locking system and now comes with wheels (wheel kit optional on SL I believe). The Starlight also seals well against dust and moisture (maybe not quite as big gaskets) but the main difference is that it is made of an entirely different plastic than the TV. Difference is that the TV plastic breaks as in cracks or chunks break right out if the case is very cold and dropped. The Starlight dents, which is much better. Not a factor unless you use them in below freezing temps and they get rough use.
Handles are different, the SL handles fold flat and the TV handles are molded so they stick out a bit. Otherwise the two cases are fairly similar in size and capacity.
I found out the hard way that you should always tape the latches closed when putting them on an airline - somehow a latch popped open and was destroyed when I got the case from baggage after one trip. Not quite as easy anymore as you can't take a role of duct tape in your carry-on. I just take a short piece to tape the latches shut after they look at the gun(s) and are going to put the case onto the conveyor.
