Paying as little as $55 a month for unlimited data and talk time sounds pretty sweet, right? The $99.99 LG Optimus V on Virgin Mobile is a budget-friendly smartphone that doesn't tie you down with a two-year contract, and is far less expensive than the major carriers. It's not the most cutting-edge handset out there: We're talking a 3.2-inch QVGA display and modest 3G speeds. If it's simple you're looking for, however, the Optimus V delivers, offering snappy performance and a responsive touch screen. But how does it compare with other contract-free smartphones?