That is some seriously interesting hardware but I don't know a damn thing about the company Slo.
Have you heard of them before? Do they have any reviewed weapons?
Personally, I would really want to inspect that upper and lower to see what kind of material is going to be used. The .338 Lapua is a hell of a round, but the torque it exerts on the action and the chamber is enormous.
We had a customer, he had "garage built" a .338 Lapua actioned rifle and put it into an AICS ( Accuracy International Chassis System ).
The AICS is a magnum actioned system, and built really well, but this guy had actually broke one of the action screws about two threads into the stock and mared up the stock pretty good while shooting it.
Apparently he just touched off a normal, factory load and "crack". The torque broke the action screw.
Since then, I have a real profound respect for the pressure of such a caliber.
Suffice to say, I am not REAL anxious to get behind the trigger of two aluminum clamshells with 2 aluminum pins holding them together......
In you know what I am saying.
It's a hell of a cool idea. And I would DEFINITELY buy one if it checked out, but I am curious, to say the least....