Dual monitor setup for gaming is tricky (if your game actually supports it). For example, in FPS games, you'd have the crosshair right between the two monitors (along the bezels). In racing, your windshield will be divided into two and will be annoying. In strategy games, maps will be cut by the monitors bezels. Furthermore, you'd have to always face at a certain angle (instead of straight on).
I think the only advantage for having dual monitors is for multi-tasking use, i.e., gaming/working on one monitor head-on while having another monitor for doing other stuffs.
If you are going to force extending gaming on both monitors, say, two 1080p monitors, the GTX 1060-6GB will struggle on GPU-intensive games in maxed settings. Note...