[Ninja_En_Short]

For my "rankings" I base myself on the official results of torture test made by military for the XM8, SCAR, the ones I don't own myself, for the other ones I own it's both the officials and mines.
It's not because the US system is corrupted enough by COLT to reject a gun that the gun is not the most reliable. Plus I had the chance to fire a few hundred rounds with the XM8 20" in USA.
Yep, lucky bastard

For the oil you can use a regular one. I use "Liquid Wrench" for the "unknown quality", first I used, tested the oil I use in my 417 in the handguard, no problem.
Most oil nowaday don't eat plastic parts since more and more guns are using plastic/polymer bodies and spare parts.
The "non-plastic-friendly" oils usually have a mention about on the label.
Just to be sure : put a drop inside the handguard and look the effect.