I finally got a Vita a few days ago and I've bene playing Time Travelers (import). Why on Vita? Because I've heard the PSP version is a bad port that runs like crap and the 3DS is region locked. Anyway, it's a pretty cool game. Initially I wasn't quite sure what to expect from it. The multi-character story and quicktime events almost made it looks like a Japanese Heavy Rain, but make no mistake: This is clearly a visual novel at heart. You don't have the freedom of movement of a game like Heavy Rain. The major difference between Time Travelers and most visual novels is how...dynamic it feels. You aren't just reading text while looking at static pictures, the game is constantly in motion. There's a ton of action: car chases, shootouts, you name it. Really, this is a visual novel with the style and presentation of a hollywood blockbuster. Or another way of putting it, it's a visual novel with actual production values. The story is pretty interesting too, and I like the way the different character stories intersect, giving it an almost Pulp Fiction-esque feel.
On the other hand, the quicktime events feel like an totally unnecessary addition. At least they're easy, I haven't failed one yet. But when they're that easy, why are they even there? Especially since you're just going to rewind time if you fail. They don't enhance the game in any way. But they also don't seem to happen that often, so they're not really in the way.
Visually the game is a mixed bag. It's bright and colorful and animations are very well-done and fluid. But I have to say, it's pretty obvious that the 3DS was the lead platform. This game does not make use of the Vita's hardware capabilities. They did up the resolution for the Vita, but with over five times the pixels of a 3DS that just makes the relatively low polygon count models and low-res textures more obvious. The models aren't terrible, but the textures are incredibly bland, making everything seem lifeless and sterile. The combination of decent resolution but lack of detail kind of reminds me of PC gaming in the 90s...on a 3DS it probably looks great, but upping the resolution and nothing else for the Vita isn't the way to go. At least it runs nice and smooth, not a hint of any slowdowns.