Ronix ATR vs. Air Core?
 

I've searched and found a thread regarding the Air Core vs. Modello (is this the same as the ATR?), but not much info in the thread.

Is the Air Core a stiffer core?
I think it's lighter, how much so?

Any other performance differences, is the bottom surface the same on both boards?

Yes, the bottom surface is the same on the air core and atr boards.. The aircore is WAYYYYYY lighter for sure like when you pick up an aircore board your gonna be shocked but I feel like the atr is a lot stronger. My buddy ride the parks aircore and he's broken every one he has. I have had my bandwagon atr for 2 years and its still in one piece. The first year I only rode it on the boat and it was great. This year Ive only ridden it like 5 times but only on cable. Its a sweet cable deck.

Bottom line.. If your not riding cable i would go with the aircore. Its way lighter and if you break one Ronix is really cool about replacing them.