Let's say you're outfitting a 30'-40' foot boat for coastal cruising. Starting from scratch, you build a system including autopilot, GPS/chartplotter, speed/log, depth and wind instruments. First question, would you stick with one manufacturer for compatibility, or pick and choose for each piece? Second, if your only choices were similar systems from Raymarine and Simrad, would you pay twice as much for the more expensive system? What's driving your decision?