Of Bach nothing more can be said, certainly not by me. But as an untalented son of a long line of Lutheran organists, I will heartily recommend Koopman's performance. The Dorian sizzles, and the second variation of Sei Gegrusset has the most appealing registration for Bach's amazing ornamentation of the melody line of the chorale. If you can follow with the score you can hear Koopman even throwing in a few embellishments of his own! The loving restored organ is a joy to hear, and the recording is exemplary. If you are a fellow bachophile you will enjoy this disc, if you are not you should acquire it and become one. You don't need the MASA missions to explore the universe - Sebasian explains it all for you.