I have been flying the 135 for 3 years and I don't think I use the Trim Release button at all only ever the collie hat, though my unconscious might do something different. On the SA365 I used to use the Trim Release button all the time but on the 135 it just makes it to floppy for my taste.
I was told though to use the T/R during autorotation in order to gain the 75kts quickly.