Qubica, as far as I know, is a lot slower than 1-2 mph lesss than what it actually is because it measures at the rear, about 10 ft, more or less, from the pin deck. The bigger your hook, the bigger the difference from the release point to the back end.
CATS measures all along the lane from the foul line at 10-12 ft intervals, I believe. Most references for a person's ball speed are at the 10 foot or the arrows (14 ft) mark; so, most people's speed at that point is good deal faster than what Qubica measures.