Has anyone used windshield washer tablets? Are they any good? They are very cheap (100 tablets for about $7) and convenient to use.
I would avoid these altogether. Use the good old fashion washer fluid in the gallon bottle. These can cause damage to the pump from undissolved pieces getting into it. Washer fluid is part of proper maintenance so going cheap is the last thing you want to do.
It appears it does lower the freezing temperature slightly to -5c (23F). I like the legal disclaimer - "Statements regarding dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease or health condition."