I finally got a chance to spend some time with a pair of T1s, driven by Glenn's OTL. This is one fine headphone. I didn't fine them exaggerated anywhere and they were not fatiguing at all. The detail they produce is excellent and they produce a nice bass. I also listened to a pair of HD800s at the same time and I enjoyed the T1s a lot more. I need to get myself a pair of these.
There is something magical with the OTL and the T1 - I think they sound great together. The Valhalla and the Crack share the topology and I've had similar results.