Sunny 16 is hit or miss at times but it is pretty damn close. just trust the meter, i found that film SLR's meters are more accurate than digitals for some reasons. the A mode in the FE/2 is pretty accurate as the shutter speed can be anything unlike full manual cameras. by this I mean the camera can select the exact speed accurately.
The BSD (Bright Sunny Day, or Sunny 16 rule) is only a guideline. Although hardly no one ever shoots slides any more, it works reasonably well. It is inadequate when shooting slides however since the exposure latitude is so small. There are other variables which must be taken into account when using it. Where the sun is in the sky (time of day) can have an impact on it as well as well as any atmospheric haze. Also, the development protocol of the film will affect it as well, depending on the developer, dilution (if any) and amount of agitation.
Usually it will get you "in the ball park" though. There is also an addendum to the BSD rule and that is the rule of thumb for shooting the moon. 1/ASA @ f/11 for full to half moon and f/8 for less than half.