M16 Cheap or Not?

I know there has been a lot of debate of the M16 being cheap or isn't. Some of my friends think it is cheap while others don't. If you don't know what I am talking about then let me explain. A lot of people think the M16 in CoD4 (the first assault rifle) with stopping power is cheap because it can be instant kill. My personal opinion is that it isn't cheap. Wanna know why? Well here are the reasons why I think the M16 is not a cheap weapon.
1. All 3 bullets have to hit the enemy
Yes all 3 bullets have to hit the enemy which can prove to be difficult when the enemy is far away or close range and especially when there running (for some people).
2. It is a burst weapon
The M16 only shoots in burst which means if you don't kill the enemy with your first burst it gives them plenty of time to kill you before you can shoot a second burst.
3. There is the Juggernaut perk
Even with stopping power the M16 will not kill you in 1 burst (even if all 3 bullets hit you) if you have Juggernaut. Unless if they get a head shot of course.

The M16 is one of my most favorite weapons in CoD4 and I still say it is not cheap. I would actually say that, that assault rifle takes the most skill because unlike the others you have to lead your shots even more so since its not fully automatic and you can not just pray and spray. Also if y'all do not know the CoD games is one of the most balanced Multiplayer games out there. There are no power weapons and which guns you are good with normally depends on your playing style. That is one reason why I love Call of Duty so much is because it's developers spend tons of time balancing weapons and do a very good job at it. So what is your opinion?