I think there exactly the same, just different names.
140s a bigger engine obviously so id go 140.
I think its the best $700 I have spent, it got me out there doing the sport, but you need to be able to spin a spanner and set it up right to get your moneys worth, If you do what my mates did and treat it like poo it will be poo.
Here is a pic of my Atomik Reign Bigfoot 160
In the not so distant future it wont be much of an Atomik anymore.