Congratulations on releasing of FX IMPACT M4 
The most important changes as it appears to me are;
1. "better trigger"
2. "reverting to single regulator" (for non technical users),
3. "better pistol grip" and a
4. "stronger top rail" that will be helpful fixing POI shift issues.
Great
Umair Bhaur

The most important changes as it appears to me are;
1. "better trigger"
2. "reverting to single regulator" (for non technical users),
3. "better pistol grip" and a
4. "stronger top rail" that will be helpful fixing POI shift issues.
Great

Umair Bhaur