expect your power to increase by 50-75%, considering a stock unit is like 5watts rms, and the one you are looking at is prolly 23watts rms and 50 max....that alone tells you how much better sounding its gonna be. you might want to replace your speakers in the long run, but you will hear a difference when you put it in.
want more power?? try this
if its in ur budget, go with one of the higher level models with the oel display, so you can impress your ears and eyes!