Red-dot aim point

Just wondering - how effective and efficient are "red dot" aim points that are used on modern assault weapons?  I am not refering to aiming lasers (though if you got one, feel free to comment) but specifically to the reliablility and effectiveness of a red-dot aiming device.  To wit - are they primarily for tactical use?  Are they aligned to match the "usual" bullet impact point?  What distance are they normally zero-ed out to?  Are they more effective/less effective than iron sights (assuming both are properly sighted/aligned)? 
 
Was watching a recent video game trailer and began to wonder that if they worked as wonderfully as they seem to be depicted.
 
Thanks,
 
Jack Nastyface

I know I once posted a detail commentary on the use and effectiveness of aimpoints and holographic sights.  I have a number of Aimpoints and EOTech holo sights.  They are both good for quick target acquisition.  Since you asked specifically about the aimpoint, I'll say that you'll get very quick target acquisition at under 30 yards, but still manage tight groups out to 100 yards...there is effectiveness on sillouettes 300-400 yards.

I'll add that with an aimpoint, you have a larger field of view, more situational awareness with both eyes open, and better use in low light conditions.

 

Jarhead,

Thanks for the post - I'll go try to find your older post but admittedly sometimes the forum search function don't search so functionally.

FWIW, I was looking at some of the COD:MW 2 trailers and noticed how the rounds tended to land right where the aimpoint was located.  I was fairly certain that there would be some variation depending on where the aim point was zero-ed in. 

I fired an AR-15 with aim point once while a friend was setting up the device.  I think he had it zeroed for 50 yards, which provided some nice groupings.  Of course, everything I own(ed) is 80+ years old, so "pie-plate" groupings with no key-holing (tumbling) is sweetness.

S/F

Jack Nastyface