The first (and only) PNY I bought was bad from the get-go. I never gave that brand a second chance. I've had maybe three SanDisks, of which one went bad (intermittantly). The most durable and long-lasting ones I've had? Don't laugh. Some unheard of brand called "A-Data". I've got four of those from back in the day when 256Mb was considered large. All four still work perfectly.

My A-Data's are similar to this one: http://www.newegg.com/Product/Product.as...1-357-_-Product but mine are many years older.