Running two smaller fish finders (one at the console, one at the bow) vs one large unit at the console is a common configuration question on tournament bass boats. Here's the real trade-off analysis.
One Large Graph at the Console
A single 10–12 inch display at the console is the simplest installation — one unit, one transducer, one wiring run, one subscription. Larger screens are easier to read at a distance, split-screen views (sonar + chart, 2D + SI) are more usable on a larger display, and the investment concentrates in one high-quality unit rather than splitting it across two.
Limitation: when you're fishing the bow (where most bass boat fishing happens), you're looking back at a unit 10+ feet away on the console. Reading depth, marking waypoints, or interpreting sonar from the bow deck requires either walking to the console or using a wireless remote.
Two Smaller Graphs (Bow + Console)
The tournament standard on serious bass boats: a 9-inch unit at the console for navigation and chartplotting, a 7-inch or 9-inch unit at the bow for real-time sonar while fishing. Both units receive GPS position from the NMEA 2000 network. The bow unit has a dedicated transducer on the trolling motor for optimal bow-position sonar. The console unit has the main transom transducer for high-speed sonar.
This configuration requires two transducers, two display units, and more complex wiring — but delivers sonar data where you actually need it during fishing (at the bow) and navigation data where you need it during travel (at the helm).
7-inch ECHOMAP at the bow paired with a 9-inch at the console is the most common dual-display tournament configuration. Bow unit mounted on RAM Twist-Lock for quick removal.
9-inch unit at the console for navigation, chartplotting, and high-speed sonar during travel between spots. Paired with the 7-inch at the bow.