These are pretty efficient speakers, and will sound a lot better than stock speakers, (in the parking lot). They are rated at 5-70 watts RMS power range.
They are designed more for stock head units and small amps like the Arc 125 that was pushing them.
If your planning on adding a amp later then this would be a good upgrade. If not, I am not sure it is worth the money and effort.
These speakers are going to be a better quality sound, but without an amp, I am not sure you are going to notice a difference at speed (60-80 MPH) because of the distortion the wind does to the sound waves.
Even a small amp makes a huge difference at 60-80 MPH