All I use is Engine Ice period. Really good shit.
As far as how much, I don't have my manual here, but I can find out tomorrow if no one posts it. If you don't have one, the very first thing you should buy is a service manual for you banshee. It is imperative to have and you'll refer to it a hundred times a day, maybe only fifty if your not as dumb as I am. Get one on Ebay, or from your dealer, but you must get one.