After my minor fiasco with the car having fluid only good to +32 F (California car where anything else is illegal), I hastily went to AutoZone and bought a gallon of the pre-mixed store-brand washer fluid. It claimed to be good to -20 F.

I have to call [censored] on it, truthfully. It was about +20 F last night and every time I sprayed it on the window, it would crystallize and ice up with 2 or 3 seconds, making it totally worthless. Mind you this is with heated washer nozzles.

Promptly went out and bought two jugs of purple Splash!-brand -35 F stuff and put it in. Low-and-behold, it did not crystallize or freeze up at all. I'm really questioning if those cheap fluids meet the advertised specs.

Anyone else have similar experiences with cheap fluids?
2011.5 BMW M3 saloon ZCP
Castrol Edge Professional TWS 10w60 + Mahle OX 254D3