The Pacer is the short-course end of New Balance's SuperComp range. A carbon plate sits in an Energy Arc midsole, the whole shoe weighs 211 g, and the forefoot is stiff enough that it only starts making sense somewhere above threshold pace. Think 5K through half marathon rather than a marathon.
It suits you if you already race in a plated shoe and want something firmer and closer to the ground than a marathon racer for the distances where turnover matters more than protection.
It is not a training shoe. The plate and the 8 mm drop are tuned for one job, the foam gives up its life quickly, and easy miles in it waste both the shoe and the reason you bought it. Race in it and keep something else for the rest.