I agree that prevention is best but if I'm there on a service call, I'll disassemble and clean it. Then I let the customer know about the products available to prevent it from happening again. I've only seen one get so bad that it caused the little spots, usually I see odor problems before it gets that bad. When I removed the basket, I found a very heavy scum buildup. I doubt any cleaner or vinegar would've gotten rid of the buildup, it needed to be physically cleaned.
Of course, this only applies to topload washers. A frontload washer is too labor intensive to disassemble and your only option is to use a cleaner.