To me T1 is a definite improvement from DT880 in some areas like more articulated, hard hitting bass, increased air and details, some weight in midrange (finally), but that freaking 10K spike ruins the party. On some material makes your ears ring.
Beyer should have added some dampening to address that like it was done on DT line.
But there is always hope
Felt is ordered, now the wait, if that doesn't work they are leaving.