i would be wary of the ATR, several folks on the forum (me included) have had probs with the blade opening in your pocket due to insufficient detent.
i took a trigger pull gauge and fastened it on my ATR and my BM 806 to test pressure needed to open it ( i know i know not scientific, but does prove a point, to me anyway) the 806 took about 2 lbs to open, the ATR didnt even hardly register FWIW, i would be wary of the SS ATR's, MAYBE the ti is diff but i have had 2 compression lock spydercos do the same ( ATR and a gunting) so maybe it has something to do w/the lock design??
too bad cause i love the design, fits my hand great, but a folder that opens in your pocket isnt a good thing imho