OK, finally managed to snag a T1 and play with it. My first impressions, especially on some of the "issues" some here have noted:
--The clip manages to be both sturdy and pliable. I don't think there should be big problems with scratching, after all HA III is supposed to be pretty scratch resistant. I've pulled it up a bit a few times, which also has reduced the friction. Finally, you can actually hold up the clip as you use your hands to twist the bezel (or even use the clip to get some leverage), preventing any contact between the clip and the body of the flashlight as you twist the bezel. There is also duct tape one could put around the clip to eliminate any remaining doubts.
--The light is about as large as I expected, but lighter than I feared. No problem even in fitting into a front jeans' pocket.
--The holster is great, very good way to carry the T1 around.
--No problems pushing in the back switch with a thumb, although to push it in all the way (ie, engage the switch to the permanent "on" position) you may need to push more with the tip of the thumb at a slight angle (rather than with the joint part of the thumb and completely at a vertical position relative to the flashlight). I suppose if you had a huge thumb it might be more of an issue, for me the space between the angled standing parts is sufficient.
--Can't comment on whether the knurling is problematic, as it was dry here and I happened not to be bleeding while handling the flashlight. But if this were a big problem, one could attach some kind of tape to increase friction. The clip also helps in this, if one uses a hand hold around the clip.
Of course, Fenix should offer extra options to reduce even any small remaining issues: a different (non-tailstanding) switch component, and a non-clip version (I read that a non-clip version already exists and will be on sale soon).
But other than these "issues" the flashlight itself is pretty amazingly great in terms of output and throw, I've been going around with it in the dark and flashing things in a kind of happy stupor, kind of refusing to believe I could be getting so much output with such long runtimes in such a nice package. I especially liked putting some light at the top of tall trees 50 or more yards away and getting a nice large round spot of light there.
Unfortunately, the squirrels were hiding at the time, it would have been fun to see them react to the light!