I think it's really personal preference. I like floor plate fitted rifles if they are the slim hunting type rifle. That being said, I also like the versatility of having a detachable magazine (ease of unloading, different ammo, etc.). I have found the 5rd AICS mags tend to fit either flush, or near flush on many rifles (see below). <shrug> Like I said; personal preference.
As to why they have become so popular? AICS type magazines are the easy button for manufacturers. The magazine is always the biggest challenge when designing a rifle, so using an established pattern like AICS, with a known geometry to ensure reliable feeding, just makes it easy on the manufacturers.

As to why they have become so popular? AICS type magazines are the easy button for manufacturers. The magazine is always the biggest challenge when designing a rifle, so using an established pattern like AICS, with a known geometry to ensure reliable feeding, just makes it easy on the manufacturers.




