Taught MSF’s BRC (basic rider course) for 4 years, took the ARC (advanced rider course) twice to help new ARC coaches learn to teach it and took Alain’s off road course with Xplor at the Romney GTG a few years back.
A couple of years back I did the Edelweiss Alps Prep Course. It was a nice one day overview of techniques for riding twisty mountain roads. It may be a bit basic for a lot of folks here, but even a training day in the Alps is fun.
I've done about six California Superbike School (Keith Code) days. Good for building confidence and some technique for road riding, but an S100RR is a lot different than a Tenere. (I should say that one day there was a guy riding his own old R12000GS who was quicker than most of the guys on on the fast bikes, proving great skill beats a great bike any day of the week.)
My favorite course in the last five years, by a long shot, was Northwest Motorcycle School (ridelikeacop.com). I thought I was a pretty good rider when I got there, but I was twice as good by the end. It's a tough course, four ten hour days with nearly all the time actually riding and practicing new techniques. The first day starts by showing you riding skills that look completely unobtainable. And by the end of day four you've got them down. If you decide to go, definitely use their bike. Just like in the dirt, the only way to really learn the limits is to drop the bike. A lot.