I've had four sidecar rigs. The first one was the most fun. A SR500/Velorex. It was so light when empty, I could pop the wheel off the ground anytime, and keep it up. Could even do left hand turns with it in the air. I also liked to take it up into the hills and slide it around on the dirt roads.
Unfortunately, after a couple years of that sort of abuse, the SR was too clapped to keep.
The others were a Ural, a Dnepr, and a BMW/Steib. Very cool, but too heavy, underpowered, or expensive for acrobatics. But they were all ridden in the snow. Nothing handles like a sidecar rig (with skinny tires) on an icy road.