I have both. Well actually for the FAL, parts from CAI were assembled by a gunsmith.
Both have actually functioned extremely well. for the CETME (stamped receiver/paddle wheel rear sight), I can only recall it failing to feed twice out of ~3000 rounds. After setting the gas knob, the FAL (no brake, Imbel Type III) has failed maybe a handful of times over ~5000 rounds. I've only soht south African, Portuguese, and Hirt through them. The Port seems to be the best.
Shouldered, the FAL's grip is just slightly too rakish for me but that is a very minor point. The buttstock that came with the gun, though, was a bit too high on the comb and I couldn't line up the sights at the 100 meter setting. replaced it with a Penguin.
For me, the felt recoil from the CETME is noticably less. It does fling the beat-up brass about as far as the bullet. Well, maybe not that far. The FAL ejects like any normal semi. Mags for both can be had for cheap. A lot more aftermarket parts available for the FAL and also easier to swap out the upper for a change of applications, though.
Both about the same accuracy-wise. The CETME is a bit more complicated (but not difficult) to take down than the FAL. Also, my CETME seems to get more dirty than the FAL, due mainly to the fluted chamber.
Either way, both guns are pretty good for under $500, IMO. A lot of people don't like the stamped CAI CETMEs due to potential problems with misaligned sights, headspacing, etc. but mine has work out well out of the box.