I started out thinking "this feels slippery and too fast for its own good" in Pursuit Mode, and "a bit impotent" in Battle Mode, but after an hour of play it started to click, and I thought, "Holy shit, this is amazing."
The Batmobile feels incredibly empowering, the way you chew up the scenery, demolishing everything in your path (yet harmlessly pushing aside pedestrians with your force field, and knocking them out with slam shells how convenient!). The entire city is designed around it, destructible at every corner so as to not slow down the Batman. There's something addictive about the sense of speed and power in Pursuit Mode, and the twitch maneuverability in Battle Mode dodging one way while shooting another, and the satisfying *POP* of enemy drones as they burst into particle effects.
I love seeing the crisscrossing lines where an enemy is about to fire, and prancing between them like a ballet dancer on the battlefield. Or shutting everyone down with an EMP blast, or turning the drones against each other. The missile lock-ons can be annoying at times, but a quick spray from the turret shuts them down. The slow-mo effect when you destroy the last drone is always nice.
There's also something to be said about the way Batman can dive into the Batmobile anytime he's near a road, whether he's mid-glide or looking down from a rooftop. The many different ways Batman can scramble into the cockpit just adds to the seamlessness of the experience. Having a mobile launching platform that can eject Batman, at speed, straight into a glide is a fun alternative to the usual grappling hook. And having a way to traverse the city at street level, other than walking or running, really allows you to appreciate the detail of Gotham City. In the other Arkham games, the fastest way around the city was grappling and gliding, which often took place high above the city. Now you can travel equally fast on the streets.
The best part about the Batmobile, however, is the "tension and release" it provides, and the way this benefits pacing. There are many sequences where you infiltrate a facility as Batman and must find a way to grant the Batmobile access. Inside the facility, Batman is outnumbered and outgunned by heavy artillery he can't defeat by himself. The sweet release when you finally get the Batmobile into the room to wreck everyone's shit is one of the best parts of this game.
Really, the Batmobile is so great that I wonder if the previous Arkham games will now feel a bit "empty" or "slow" without it. Just having the option makes the experience so much more exciting. It's a great addition, without a doubt.
