I have had both spectrums in the Sabatti rifle. My first one was a disaster, it would not regulate and finally the top rib shot loose. Cabela's gave me the option of a complete refund or a replacement rifle. I chose the replacement.
The new rife I am extremely pleased with. it regulates well and after several hundred rounds seem to be holding up well. I don't know about the "X" in the serial number, mine doesn't have it and no grinding at the muzzle. It did have "Opti" wood, which is a very plane wood I understand from the "Med" that is put through a dip process, which lays a micro plastic film with a wood grain on the stock. I did not like the phony wood grain. I had access to some very nice walnut and re-stocked the rifle myself. I also did not like the rear sight so I made a two leaf express sight for it. I am very pleased with the rifle I now have.
Bob