I wish the Mouse Sensitivity slider had a lower range. Even with both sliders all the way to the left, the ADS sens still feels way too high. I use 1600dpi for fast desktop browsing, but always set a very low in-game sens for fine aim and this RE2 demo is the first game I've run into where I can't set the sensitivity low enough without just dropping the DPI to 800.
Having a mouse with a DPI toggle button has been a godsend for me for this reason. I toggle it between 1600 DPI on my desktop and 800 DPI whenever I play a game.