Yes, these parts should be compatible as long as you are using a mil-spec lower receiver.
Yes, the grip included is a BCM Pistol Grip, Mod 3.
Yes this parts kit will work for any mil-spec AR-15 lower receiver.
I've bought these kits previously. Mine did not. Additionally, in the parts listing, #5, just says pins.
Most of the parts included with this Bravo Company Gunfighter AR-15 Enhanced Lower Parts Kit would be compatible with your Aero Precision M5 lower with the exception of the bolt catch, bolt catch roll pin, Take Down/ Pivot Pin Detent, and Take Down/ Pivot Pin Detent Spring.
The Bravo Company Gunfighter AR-15 Enhanced Lower Parts Kit will work on an AR9 lower that has Mil-Spec dimensions.
The Bravo Company Gunfighter AR-15 Enhanced Lower Parts is designed to work with Mil-Spec AR15 lower receivers. Since AR10's don't necessarily have Mil-Spec dimensions, the Bravo Company Gunfighter AR-15 Enhanced Lower Parts might work but fitment can't be guaranteed. However, the AR10 Lower Parts kit located at the link below would be a better option.
https://www.opticsplanet.com/tacfire-ar-10-lower-parts-kit-with-pgar-b-pistol-grip-lpk02b308.html
This grip is at a 5 degree angle.
Please email us Techsales@opticsplanet.com and we can further assist you.
It depends on the lower, but if it a standard mil-spec lower this will work.