I've been listening to the T-1s for a few days and I'm in agreement with Asr.
IMHO, the T-1s are nothing more than upgraded 880s and share the same sound signature. They have less bass, but more soundstage, transparency, and detail. If you like 880s you will probably recognize the T-1s as an upgrade and like them too.
Unfortunately, they are not the order of magnitude better that their price implies. I think they are over hyped and over priced at $1300. If 880s can be had for $249 on ebay, these should go for around $500.
One thing I didn't care for with the T-1s was that they were not very good for the low level listening I usually do. When I turned down the volume, the mids faded out, disproportionately to the top and the already sparse bottom diminished even further, throwing off the tonal balance. Another thing I didn't care for (with low level listening) was a seemingly exaggerated sense of dynamic range. What I mean is that the quieter sounds became difficult to hear and the louder sounds seemed too pronounced. Again, the balance was restored as I increased the volume but I never noticed this problem with 650s or 880s.
Are they worth keeping? Sure, if you don't mind spending the money.
Btw, very nice review Ari.
[stuff used: Laptop > Hiface/Thingee > North Star MKII > 2 box M^3/GS-1]