I've recently sent 2 guns back to S&W for repairs. The first one had a door to door turn around of less then a week, the second, right at 3 weeks. S&W has first rate customer service.
I sent a mid-1980s model 60 back for repairs and they received it one month ago today. After a phone call to customer service they say it will be at least two more weeks before they look at it.