I posted a while back looking for a 2x10 scope for my 556 DPMS M12. Someone suggested I consider a 3x? So I am. I would like an illuminated rectical. If it was calibrated for the 556 that would be a plus.. $500.00 is the budget. Less is always a plus. A little more for a much better optic ok. Don't know a lot about optics. Thoughts / suggestions?