does weight reduction equel to less stablity at high speeds.. just wondering if is worth doing on a daily driver.. especailly if i have to drive long stretches on the highway..

 

Yes, all other things being equal.

That said, depending upon what I felt was the nature of the instability, I personally would find fixes in the suspension (proper alignment, better shocks, higher-rate springs) and aerodynamics (front air dam, possible lowering of vehicle, some sort of rear appendage that actually makes a difference) of a vehicle before weight would be a consideration.