I am a lever guy and have never used a Strega, but have used the Pavoni's, MCal's and Cremina. Personally, if could own another lever (on top of those I currently have) I'd go with the Strega. I can't imagine that it wouldn't be way better than any of the domestic spring levers such as the MCal and Ponte Vecchio Lusso and Export. It is a bit of a game changing machine, a domestic (or better prosumer) machine with a commercial lever group and commercial lever springs. This just must transfer into superior shot making capabilities and superior shots.
Of the others, the Cremina is the king of domestic, small-sized lever machines for any number of reasons that have been well-documented on this and other forums. But it is extremely expensive new, and hard to find second hand. They cost around $1000 more than a new Strega, a price differential many out there are not prepared to pay, especially since the Strega is more versatile machine in terms of what it can do (eg churn out far more consecutive, high quality shots).