Detachable 2-in-1 laptops try to do the job of both a tablet and a notebook. The Lenovo Miix 510 doesn’t quite deliver the best of both worlds. While this slick-looking hybrid offers fast performance and a colorful display, the machine’s battery life and keyboard leave much to be desired. Starting at $599 ($723 as tested), the Miix 510 is a solid choice, but there are better options at this price.