Board Thread:General Nerf discussion/@comment-27035444-20160823015421/@comment-27103116-20160823031347

The Zeus is your flywheel semi-auto, so a RIVAL Stryfe essentially, while the Atlas is the RIVAL equivalent to the Diatron, a two-shot "shotgun". Neither take Apollo mags, so you'd be sh*t out of luck there, and the Zeus has the problem of "slappable mags", meaning that per standard attempting to smack a mag into position will smack it out the other side (nothing some duct tape and an old Rubbermaid lid can't fix). The Atlas has an efficiency problem - 12 round mags only hold 6 "shots". Also, the jam door is pointless - unless a ball falls out, there's nothing to get at.

TL;DR, it's a matter of opinion. They both have strengths and weaknesses, it's what you want from your RIVAL blaster.