Thanks for your impression! I too find my df 1.2 less warm than my stock headphone out on my surface pro. Better clarity though!
Given we have similar headphone preferences, I'm now more excited to get the TH900 and supremely jealous that you have them... and not me haha
With no TH900 coming here soon, I put jealousy down and picked up a bowl of green tea to endure the wait.