How do Nokian's warranty and customer service compare to other brands?

I've been doing some research on various tire manufacturers' warranty and customer service policies and I'm curious to know how Nokian's compare. I've heard great things about their product quality, but I'd love to get a sense of what actual customers have experienced in terms of support and coverage when issues arise. Do they offer competitive warranties? Are their customer service representatives responsive and helpful? Any first-hand experiences or comparisons with other brands would be greatly appreciated!