Its really all about the feature set.
In the 80s the FE would give you 125th flash sync (IIRC 250th on the FE2) against the F3's 90th.
The FE was the cheapest body with interchangeable focusing screens but the F3 gave you a removable prism housing and a wider choice of screens.
F3 had mirror lockup, FE didn't.
F3 had a flip up tab on the metering ring to allow use of pre-AI lenses, FE didn't.
F3 had high-eye-point finders, FE didn't.
And most importantly in the news/sports world, F3/MD4 would get you about 6 fps, the FE/MD12 got you 3.5fps, depending on the freshness of your batteries.
There were always stories (prob BS) of F3s being used to bludgeon rodeo bulls into submission and remaining functional. OTHOH I actually saw a still functional FE that a photog had left on on the roof of the car as he sped back toward the office - leaving the camera rolling along the blacktop.
Bottom line, buy the features you'll use and go make pictures.
Image quality is in the lens, the film, and ultimately the operator.