I'm sure if you are going to simply store it over the winter then a coating of acf50 will work fine. It's the high speed jet of salt water from the roads that causes the problems. It tends to wash the acf50 layer off and you need to keep reapplying it throughout the winter - if you ride. You can acf50 the complete bike in about an hour with a small paintbrush, because you only need to do the bolt heads and poor quality steel brackets. Most of the bike is well finished (so you don't need to do rims for instance). If you have one of the newer bikes with stainless spokes, it's worth doing the spoke nipples(?) where they go into the rim, as these are bare plain steel. I have found the rear sprocket and bolts is pretty bad for corrosion - not red rust but a sort of grey/black corrosion that is impossible to get off once it's established. ACF50 should help there if it's not going to move, but I have some Honda Moly60 grease which I have painted on and so far seems to be doing the trick.
Mike