The box frame on the Lifestyle models was dropped mid 2016 model year. At the same time, the full wall slide models were dropped, too. It will be obvious as the late model I-beam frame models loose the side rear baggage doors.
Another thing unique to the former Carriage and 1st generation Lifestyle models is that the slide mechanisms sat atop the frame, therefore, no hole cut into the side of the frame to accommodate them.
The 2nd generation, or Titan II frame, has a hole cut in the side of the I-beam to accommodate the them just like the majority of all other makes.
I spoke the Quadra/Big Foot rep and was told that Lifestyle dropped them. I love my Bigfoot and have had no trouble or frame torque raising the front with one jack when I pulled a wire loose.
At any rate, Lippert has come out with a new system similar to the Big Foot where as each jack is self contained like the Big Foot product.