I too recommend shooting your SPX "stock" before adding things. That way you'll know if somethng you did caused the gun to fail. I too am on my 2nd SPX. first one was a lemon but Mossberg made it right by replacing it with a new gun. My current SPX is my go to gun for HD/SD and 3 gunning. My Benelli S-90A1 is now a "safe queen".
If all works well I think your choice of accessories is well chosen. Good luck and give us a range report before and after your additions.
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NRA and CA. P.O.S.T certified Pistol, Rifle, Shotgun, Tactical Instructor.
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