I don't know what their policy is now or if it was different among the boutiques, but twice I went to an OB and they took my watch in, checked for nominal water resistance (not 300m), checked it's timekeeping and amplitude, some other things free of charge while I waited. It at least confirmed my 2298.80 needed service at the time. They even replaced some missing collars on the bracelet for that watch. Worth a try, if you really want to know the running condition. Six years is approximately when some service anyway, some wait ten or more, others until it's noticeably "broken" or not running. Some have more of a concern regarding water resistance and want to stay ahead of that. I think only you know how often you've worn and ran the watch or if water resistance is a concern and can make the judgment. Also consider what the alleged service six years ago might or might not have entailed. That's how I would approach it.