The effects will vary between maps and the number of objects available to run over or into. Titan has been the worst for me in this reguard and Sahara the least.
When set to the lowest setting the game becomes unplayable due to the built in cockpit shake routine verse map objects. The effect basically causes your mech to stop/shift/bounce all at once (at the lowest setting) and feels like your are running into the floor like a bulldozer at full speed with it's blade set too low. This initially seemed to me to be game lag until I remembered changing that particular setting. It also seemed to cause the mech to partially run into/through a wall at times causing movement issues. The effect is amplified under boost.
Setting the slider to max smooths out gameplay immensely, but the lag effects are still noticeable on maps like Titan with uneven floor surfaces.
Edited by RipperT, November 13 2012 - 08:58 AM.