Top end power is the horsepower that catapults you into passing gear on the highway. Low End grunt is the torque that flattens you in the back of your seat pulling away from the lights. Which do you want?
Your choice will dictate your intake manifold choice. For a street car, the priority should be torque, since 90% of street driving is from a stop, or at 'part-throttle'. An intake manifold built for torque will put a smile on your face every time you pull away froma light or hit the onramp.