I picked up the MW4 compilation today for a cool $20, and have played through the first few missions, I really want to love it, but the tedious turning and torso turning is annoying, and turning with the keyboard is extremely slow, is this a known bug, or a design choice? Is there any way to hack the torso turning so it is more sensitive? This is the most annoying in the city, when precision maneuvers are required. I am using a Microsoft Optical Mouse if that helps. Maybe I am just too impatient, but holding down the turn key as my Mech slowly meanders over and then watching it walk into a wall as I try to turn torso to fire is teeth-grittingly annoying. Thanks in advance for any help.

Turning and torso turn speed is dependent on the 'mech chassis you are using. Generally assault 'mechs are slow and lights are fast.
So unless all mechs seem to have the same slow speed; it is a design choice.