I have a metric ton of Leonhardt's Bach, thanks to various boxes I've picked up inexpensively over the years. I listened to it a few times, but it always sounded sort of cold and mechanical. Not unlike Gardiner's Beethoven....
Right now I am listening to the SACD of Leonhardt's WTC and I have to say it is kind of revelatory. There is a richness and "wash" of sound I never heard on the standard rez versions, which shows how much he is playing around with harmonies, leading to a much less cold and mechanical sound. I'm really glad I got this set, and kind of sad that there isn't even more hirez available at reasonable prices.