As for running at turbo for longer they both run roughly the same amount of minutes at turbo before the TN12 starts ramping down to the next setting and the PD35's electronic regulation drops it from turbo to the next setting no matter how hot or cool it is. Keep the Tn12 cool enough and it will indeed run at turbo for longer.
The TN12 doesn't have any defined stepdowns. It will eventually lose brightness gradually as the cell becomes depleted, but it never ramps down to a lower mode, whether you cool it or not (there is no thermal management). It will therefore get quite hot if you don't have any cooling...but it will run at higher output for longer - selfbuilt's graphs show that quite clearly.
It is funny that you mention the large hotspot of the PD35...I still have a PD32UE, and I like it BETTER than the newer PD35. It has an even larger hotspot, and I lucked out with the tint lottery...one of the nicest beams in my whole collection.
It is good to have choices! There are many solid contenders in the class, so there should be one that is suitable for just about every buyer out there.