After doing the antenna mod to my ST16 to give me 3 external antennas I wanted to range test my setup. I did several runs out over some back woods and swamp land. After one run I was on my return and suddenly my H voltage dropped to 14.1 and said to land immediately! I felt sick since I was a good distance away and flying over some extreme backcountry gnarly terrain. I've never been in a situation that I had to land in a remote area by FPV (I could see the H in the sky but the only way to tell what was directly beneath it was using the st16 screen with the camera pointing straight down). I paused and panned the camera around looking for a safe place to touch down. I started to descend to a location that seemed like the best option. Then just a quickly as the voltage had plummeted it shot back up to 14.8! All the warnings went away and I flew back and hand caught my H! Had I been forced to land I don't know how long it would take me to find and recover my H. I'm thinking maybe it's time to invest in a Marco Polo. Who uses one? Do you like it? Is it our best option? Anybody ever experience a huge battery voltage drop and then rebound while flying?