depends what you are after.... stock they are quite nice, they have good bottom/midrange and a reasonable top end...... Some people love them the way they are, others find them to be a little too mild....I cant speak for others but my modified version is a pretty substantial bump in power and RPM over stock....bottom end we gain a little, midrange we gain a fair bit and the top end of the modified absolutely sings compared to stock.......The modified version carries all the same characteristics as stock, except its a whole pile faster......... Some love them the way they are, others will like the modified version better..... just depends on how much juice you want .