Go with the SPS. Smooth action, free floating stock, great price. You might want to consider a trigger job. Most all guns have "lawyer" triggers (9-10). A lighter trigger will help accuracy, and it is a cheap thing to do. As you may have seen in my earlier post, I'm fixin to do this to my rifle soon. As for caliber, 300 mag!

Shotguns-Again Remington 870- cant beat the performance, especially for the price!