only fair way to do the comparison is how it will be listened to in your home. If you are going to listen to the standmounts with a sub, it is critical that not only do you have the sub on hand, but you spend the time to integrate it with the standmounts. Take the time and that will give you both a fair sound and budget comparison.
If you don't, odds are you are going to gravitate toward the fuller sound of the floorstanders. Not that this is a bad thing but you are essentially stacking the deck against one option.
If you don't, odds are you are going to gravitate toward the fuller sound of the floorstanders. Not that this is a bad thing but you are essentially stacking the deck against one option.