Having owned none of the aforementioned, my thoughts are just random.
But, do NOT discount the Super X4. All the Super X series guns are about as much bang for the buck as you'll find.
The A300 is made, in part, in North Carolina in a friend's machine shop. So, there's that.
But, a parting thought is.... Do you already have a lifetime supply of 20 gauge TSS loads bought ?? In the current "tungsten climate", it's beginning to occur to me that 12 gauges and lead Longbeard XR's may be about to make a huge comeback. 🫤