Yes, the Panzer Arms M4 - Tactical Adjustable Telescopic Shotgun Stock Set is adjustable for comb height allowing you to adjust the height of the cheek rest. This will assist you in lining your sight picture with whatever height optic you are using.
No, it absolutely will not. I have this installed on a Panzer M4 Speed Pro and am very happy with us, especially at the price point. But, with the stock fully compressed and the cheek riser all the way down, I cannot get a line on the rear iron sight whatsoever. Positions 2 and 3 let me see just fine and an elevated optic (ar-style) would possibly be viewable from position 1, but I would call the fully compressed position a storage feature only. It'll still fire fine, but you'll be point-aiming, not aligning iron sights.
Not iron sights, but with red dot yet.