I've heard mixed things about the T5P. The main thing about the T1 was I just kept looking at the HD800s while listening to them... It almost felt "fair" to place the T1 in between the LCD2 and HD800 in terms of differences, but of course the T1 was closer to the HD800 than the LCD2. I kept feeling that the T1s were trying to keep up with the HD800, even though both of them are great headphones.
Did the T1s have more treble than the HD800s? That would be my threshold for treble quantity. The T5p/T50p had horribly peaky, wonky treble, even more than the HD700s, and I couldn't even try to listen to them for any much longer, but I wanted my impressions to be fair. Worst hour of my life, just thrown away right there. HD800s and T1s, along with the HE-6s, are definitely in consideration for my partially complete end-game rig with the LCD-2s here.
Sorry OP, for going off-topic. I'll try and keep it out of the thread.