AFAIK 100kph talaga speed limit sa mga expressway but still NLEX and SCTEX are giving motorist 20kph more...so bale if na radar gun ka ng 120kph dikapa overspeeding until you reach the 121kph and above mark...they will just enforce overspeeding at 121kph and above...

di ka naman perfectong tao to just maintain your speed at 100kph para bang may buffer ka until 120kph so pwedi mo laruin speed mo ng 100kph-120kph...

by the way a friend who works at NLEX as patrol saw many accidents na naputukan ng goma running at high speed at yun roll over mga sasakyan...