Thought I'd post a couple of pics of my latest creation, a fillet brazed frame with Di2. My first ride with mtb Di2 derailleurs and it works great I was very surprised how easy it was to setup and how well it works. Hardest part so far is getting used to which switch moves way. I was also very surprised that it works so well with a 10-42 Sram sd cassette and Sram mtb cranks. I had the Sram parts and figured I'd give them a try and if it didn't work buy Shimano later, no need though. It will fit up to 2.1 inch tires, limited by the fork the rear will go larger.
This is my first built up fillet frame and so far so good.