Mine had an electric valve when it was new. The guy I bought the boat from said the electric one took a shit so he just put a T valve in its place. Both tanks drain almost evenly when you're running it. I ran close to low fuel one time, so I went to hose man and bought valves to shut off the empty tank in such event.
Since then, having the valves... I'd rather not have to worry about fuel, especially since I'm almost always boating in current.. keep the tanks full! If I'm getting a burger and a beer or four, I put a small fortune in the tank to make sure I get from needles to Laughlin. Nothing worse than having 1/10th of each tank left and someone wants to ski or wakeboard before the boat goes on the trailer.
A river trip from socal for a few days is never less than a grand for me. Just depends on what you do and where you go .. I spent 40 bucks on valves and I've never turned them because I buy fuel when I can...