Any experience with Troels Gravesen's DIY designs?

I am intrigued by the page

Any expereince with his designs? Especially the TJL, his own favorite according to ?
I have. The 2.5 & the Acapella. The second I liked enormously. I didn't diy these myself, so I can't give inside info. ASAIK, the Acapella guy followed instructions to the letter (using the scan tweet).
What would you like to know.