I've got both, just started carrying the red one last week so I can't comment on the durability. I've been carrying the CE for about 6 months with a bunch of keys, a small knife, and it's lost anodizing on the ends and edges, isn't close to the durability of an Arc, but is tolerable. Physically, the lights are identical to my eyes, except for the different emitter. They work the same, with the usual excessive 5 Fenix modes.
When I first got the new light I put brand new fresh alkalines in them just to compare. Didn't do any beamshots and I've since given the CE to my daughter. The Q4 was clearly brighter. The light that thing puts out is truly amazing given it's size. It puts out as much light on high as an older Nuwai 2X123 light that I"ve got laying around. The CE is far from a slouch. I've run it on Energizer lithiums but ended up using some NIMH rechargeables which worked great. The new one is now running on Eneloops. They both provide a great useful beam with excellent spill (as you'd expect from a tiny reflector). I carried several Arcs for years, including a Miller modded twostage which was a great light as well. These are so much brighter that I'm willing to put up with a slightly larger light in exchange for something that is as bright as a Mag 2C. They are both great lights, but for the same price, get the red one. You'll get used to the color.
