Did some research on the 4 X 4. Seems this rifle is the same as the ATR, but with more features like a fluted barrel with muzzle break, an adjustable trigger, and a detachable magazine. The law suit involving a blown bolt was with a drunken guy who took it apart, and did not put it back together again, happened in the mid 2000's .
ATR guns were originally from a Connecticut company called Rapter Arms, they went out of business and Mossberg bought them out. From what I have read Rapter had serious problems with quality control, everyone mentions that they had metal shavings in the action, poor fit and finish, etc. while under the Rapter control. Mossberg probably thought they could do better and bought the design. The reviews on them show a positive light in terms of materials and design.
Practically no response to this forum on other people asking questions about them, not sure if they are rare guns at this time, but have been around awhile. Most internet mention of "Mossberg" involves their shotguns, and the You Tube videos usually show some guy putting an ATR on a table and saying it went bang and he shot a deer with it. With the 4 X 4 I hear better comments, and it was recommended by a guy I was shooting with who had a top of the line Browning BLR with him to break in that day. I figured a fellow like that who has money and can choose anything who recommends a lower end rifle must know something.
Hoping to take it to the range and see how it does next week, if it is a good one I will buy a set of dies and handload.