SUVs don't typically perform all that well in the "moose test," but the Tesla Model X isn't your typical SUV.
The high center of gravity common in trucks and SUVs can be problematic during evasive maneuvers. Some SUVs and trucks roll over at speeds of under 40 mph during the "moose test."
The Model X showed no signs of rolling, likely due to its low center of gravity from the placement of the heavy battery pack. However, the X is not the nimblest of vehicles. As such, it couldn't muster more than 43 mph in this "moose test."
#Tesla Model X in the ‘moose test’
For comparative purposes, the 2014 Jeep Grand Cherokee performed the "moose test" at speeds as high as 44.1 mph, so the speed of the X isn't exactly brag worthy.
Here's a link to massive list of moose test results.