get the alternator. you won't regret it. you might spend just as much frying the yellow top as you would upgrading the alternator. think of it this way: you dd all the time, and bump real hard sometimes. it's friday night, and you bump hard all the way to the store and back. not only do you not reover the power used to start it up, but you overdrew the alternator and pulled off the battery the whole time. if it freezes that night, the battery could be done... otherwise, it's just left in a partielly discharged state overnight. that won't kill it, but a year later, it might show signs if reduced output, and possibly not hold a charge for a week or so.. now you have the 250a alternator might do like 150 at idle and like 200 at cruising speed (2k rpm). this takes care of the typical recovery, and a good deal of bumping, without having to tap out the battery..... now if you "demo" full tilt, it's still going to pull from the battery, but that's what that battery is made for, and should recover pretty easily with the bigger alt. do you need it? no, you can get by with stock. however, you will really benefit from it. either way, i keep a digital volt meter plugged in so i can see the voltage in real time. if it drops below the low 13's, you are starting to pull off the battery. 11's, you are probably clipping and drawing more power and putting out less.