The Synaptics Touchpad Driver
Acer offered for my 5920 wouldn't install in Windows 7 x64. I didn't like the driver Synaptics offered for the same reasons you mentioned. What I did was go back one model number of laptop on Acers site to get a slightly earlier version of their driver. It worked out perfectly for me. The Acer driver that wouldn't install was v14 something and the one that worked was version v184.108.40.206.