I tend to shy away from the Informational cut scenes, since I worry that I'll lose their interest just rolling up the plot wagon and spoon feeding a great big dump of boxed text. But, if I keep it short and to the point, I think I could avoid that.
I do a lot of informational cut scenes, actually. And my players actually will ask for them if I don't do one for a while.
You're right in that you have to keep them really short and to the point. My cutscenes are always less than 5 minutes long. Usually they are only about 2 to 3 minutes long, if that.
The main reason I like using them is that if you have villains or antagonists in the game, the PCs rarely interact with them. And really, why would they? If you see a bad guy, you're going to go try to kill them. A quick cut scene, though, can
demonstrate why a villain or antagonist is really a nasty guy.
Also, cut scenes help me really express to the players that they live in a living breathing world. A lot of my cut scenes are not a big railroad of boxed text. Instead, usually, a cut scene happens as a direct result of their actions. For example, the PCs might steal something from the palace. And then, there's a later cut scene when the snotty prince finds out that his precious scepter was stolen and he throws a tantrum. In this way, a lot of my cut scenes are alternate awards for the players. Instead of handing out treasure or XP, I show them precisely how their actions have affected their world. For example, let's say the party has inspired the village to stop cowering before the goblin bands and to fight back. A cut scene showing the villagers rousing themselves out of their houses and not taking any more shows the players, "See? You make a difference. Your choices matter. You really can change the world."
So that the players don't have to worry about character knowledge vs. player knowlege, whenever I do a cut scene,
none of the information therein is unknown to the PCs. Or if it is unknown, it doesn't remain so for long.
For example, I might have the PCs come across a ruined village and then do a quick cut scene of how the village was attacked. In this way, the PCs pretty much know everything the players know. If there's someone whose identity I want to keep secret, then I have that character remain hooded or have their features blacked out in the shadows during the scene.