I also have Sylvania Silverstars. I first got them in January and the low beams blew out in March (2 Months). But, I got replacements for free. How? If you buy them at Pep Boys (Rice City) Sylvania has a 90-Day warranty, so if they blow out, just bring the burned out bulb or bulbs with your original receipt and Pep Boys will give you new ones free. After 90-Days you're SOL!
I hope this helps everyone, so they don't have to waste another $50.00 for a set.