The Nikon F3 and the F4 are both great cameras. At one time, I used the auto-exposure Nikon F3 as a backup to my F2 bodies. Today, I use the auto exposure/auto focus Nikon F4 as a backup to my F2 bodies. I hope my following notes on the two cameras are of use to you. Others have probably covered many of the items in my notes, but I list them anyway.

F3 pros:
1. Has interchangeable viewfinder and view screens.
2. Has a highly selective center-weighted meter.
3. Less electronics than the F4
4. The F3 has the option of being used without a motor drive.
5. When the MD-4 motor drive is removed from the F3, it is smaller in size and lighter in weight than the F4.
6. Has traditional brass top and bottom covers.
7. Has leatherette covering on body
8. Is less expensive to repair compared to the F4.
9. Can use linear or circular polarizer.
10. Works well with AI/AIS manual focus lenses.

F3 cons:
1. Battery dependent but has a mechanical shutter speed that can be used if the batteries die.
2. Slower flash synch than F4
3. TTL flash system is very primitive and does not allow for the use of the light meter when a flash is attached and turned on.
4. Like the earlier F and F2 bodies, it has a non-standard accessory shoe around the rewind crank.
5. Viewfinder display is not as informative as the F4.
6. Does not have an auto focus mode for auto focus lenses.
7. Cannot use G lenses.

F4 pros:
1. Has interchangeable viewfinder and view screens.
2. Has classic 60/40 center-weighted light meter.
3. Viewfinder display is more informative and is easier to read than the F3.
4. Faster high-end shutter speeds and faster flash synch than F3.
5. Normal ISO hot shoe and more recent TTL flash system
6. Does not need expensive and rare AS-17 adapter to use normal flashes in TTL mode.
7. Better balance than F3 when long lenses are mounted.
8. More metering modes
9. Has faster flash synch speed and a more advanced TTL flash system than F3.
10. Works well with AI/AIS manual focus and auto focus lenses.
11. Can use G lenses (in Programmed and Shutter Priority modes only)

F4 cons:
1. Battery dependent
2. Too conspicuous for clandestine candids
3. Not able to wind film manually
4. Cannot use camera when the batteries die.
5. More expensive to repair than F3
6. LCD bleed problems are common
7. Even with the smallest battery pack (MB-20), the F4 is still heavy.
8. Can only use a circular polarizer.
9. Rubberized covering gets a bit slippery.
10. Has plastic top and bottom.