Innovate LC-1 with an in-dash gauge. There is no value in two sensors in a dual exhaust system IMO. You're tuning both sides of the carb the same anyway. Plus the signal is going to be an average of 4 anyway.
Maybe Im not understanding you completely. Using only 1 sensor for 1 exhasut bank will only give me readings for that exhaust bank. Now, I think that could get me in good ballpark of the overall mixture ratios of the entire engine, but the readings from one bank doesnt guarantee that the other bank is putting out the same.. I want to be able to monitor both banks.