Yes Tron, that slimline J-pole setup was the solution for a lame Fortec univmount. The univmount was barely enough for the dish without motor. Not only would the side arms allow the pole to twist, but the foot and pole had oversize bolt holes for a single bolt that ran through the entire assembly. When you tighten the bolt and nut, it crushes the foot and pole because there is no spacer inside for the bolt to clamp down on.
What is good about the slimline mount is: There are two places on the foot where bolts fasten. And, there is a block inside the pole that the bolts on the sides fasten to.
OP, about that aussie mount you linked to, I would be wary about the pole twisting in the mount. You could put sand paper between the pole and mount for some grip. Or you could drill a hole in the clamp/pole and drive a sheet metal screw into it to pin it.