Well I'm hand retarded (lefty) so I like the charging handle. Well to be more precise, I like the part that wraps around to the rear and to the right. The part that extends to the left is an example of another type of retardation. You can go ahead and cut that piece of metal off, just keep the part that's actually useful. 50% of the marks for this one.
I find it extremely awkward to hit the bolt catch with my left index, while wearing gloves at least, because of the ambi mag release. The ambi-mag release really clutters operation. This mod is useless because I press the original mag release with my right thumb, which is already conveniently placed because my right hand is already wrapped around the magwell. Get rid of the ambi mag release. Zero.
No complaints with the ambi selector, spares me the trouble of placing my thumb on the left side of the pistol grip, and then back to the right side again. Good mod. 100%
And I too would fancy knowing how a rail causes spontaneous combustion?