Recently purchased a pair of Era 300s using a 15% upgrade code. Three days later I got an notification of a campaign to double the upgrade discount.. naturally I felt a bit unlucky about missing out on that, as those 300's aren't exactly cheap!
Sent a quick web note to Sonos, who responded with an immediate offer to refund the additional 15% - which was carried out promptly to my very great satisfaction.
I found this gesture to be remarkably decent and I think it's fantastic that you empower your employees to resolve these things so quickly. Well done.
Sincere thanks.
Ps the speakers are excellent, they add much more control and clarity then my old Play1s, and their range and authority make them a better match with the Arc. My movie and music listening has been given a nice upgrade.