I live in North Texas and for years kept my trailers parked in my driveway with no protection from the storm winds we get here (regularly 60-70+ each year). I used mobile home anchors (the auger type that are about 3' long) and put them down in the ground until the connector was all that was sticking out. I used a 1/4" steel cable and made it to length so that I could pass it over the frame of the trailer and then when I extended the jacks to level the trailer while parked it would pull the cables tight. Many times I found the augers pulled in the dirt (there was a small gap around the top showing it had moved) and also marks in the frame from the cable being pulled on very hard. I have had neighbors lose all kinds of things from their yards and lost part of my roof one year and my trailer was just sitting out there in the driveway taking the full brunt of the storm winds on the broad side.
My vote- ground anchors at least 3' long and strong steel cable with proper cable clamps installed tightly.
