Yes The I5 Version might not run at max settings because beamng's andvanced physics but the i7 should
16GB of RAM is becoming the new norm for high-end gaming. 8GB is mid-low end, and 4GB is just pointlessness now.
A 4x4GB kit will support dual channel. As will a 2x8GB. No 12GB kit will support dual channel for all of the RAM.