Honestly, I seriously doubt one is going to notice a significant difference at this level of lighting. Ie., I'd be surprised if you found yourself kicking yourself in the butt thinking "Man oh man WHY oh WHY did I buy the ATI instead of the Aquactinics?" (or vice versa).
I could be wrong, but that's my take on it nonetheless.
I'm sure either fixture will give very good results.
If it was me, I'd go with whatever fixture suits your budget, tastes, and what's easier to order. If they are otherwise equivalent in these factors then I dunno how to pick one over the other. Good luck! And I can't wait to see the tank in action!