Strange that Iran soldiers seems to have so many different rifles. Most armies tend to standardize their rifles for logistical reasons (similar spares, caliber of bullets, etc). Although their special forces uses specialized weapons (sniper rifles, infiltration, etc), the bulk of the armed forces uses the same rifles (for example, US marines, navy, army, air force all uses the same rifle, the shorter version of the M16).
I saw pictures of military parades with soldier marching and all, and they all have different rifles. I saw AK-47s and what I believe to be a version of heckler & Koch at the very least.
Personally, I love the M16. Even better with the M203 grenade launcher, though I must admit it's rather heavy with the grenades and all. But the feeling you get when you hold it in your arms.....
Anyway, thanks for a great website. Very informative.