grayroad: All the current production front sight are the "A2" type. The rear field sights, which are incorrectly called "A1" (they were original to the M16, not the M16A1), have not changed.
What you have is a new production upper with a new production (4-notch) front sight base, and a new production C7-style upper receiver with field sights and a brass deflector.
The C7 (Canadian military version of the M16) uses field sights for simplicity, but incorporates the brass deflector for left-handed shooters. It's a bit simpler to set up, and a bit cheaper since it has fewer parts.